P2135 Limp Mode: Throttle, Sensor, Wiring or Software?

P2135 says the throttle's two position sensors do not agree. GM prints it as "Throttle Position (TP) Sensor 1-2 Correlation", Mazda as "Throttle/Pedal Position Sensor/Switch A / B Voltage Correlation", Mercedes-Benz as "The values from the position sensors of the throttle valve are implausible relative to each other". It names a disagreement, not a part. Most modern cars have no cable between your foot and the engine: the computer opens an electric throttle, and the throttle reports its own position with two sensors so the computer can compare them. When they stop matching, the result you most often hear about is reduced power (limp mode), a wrench or engine light, or a throttle that does not answer the pedal; some cars show only the light.

This page answers four linked questions: why is the car in limp mode with this code, and is it the throttle body, the throttle position sensor, the wiring, the pedal or software; can I drive it; what does it cost. The pedal has its own pair of sensors and its own code, P2138, with its own page. The throttle's motor circuit codes (P2101, P2111, P2112 and their neighbours) are a different fault; the throttle body price is in our throttle body replacement cost guide.

The headline. We sorted 3,414 federal owner complaints received from January 2015 to 4 October 2026 about throttle trouble or reduced power. 3,197 describe this fault on the owner's own car, and only 79 print P2135; about 2,600 (81%) print no trouble code we could find. In 1,197 (37%) a throttle body was named as the cause or replaced; in 132 (4%) only the throttle position sensor or its cover; 1,239 (39%) never state a diagnosis. Of the 1,816 that name a repair or a cause, 66% name the throttle body. The full split is in the table under "What 3,197 complaints show". These are complaints, not cars or failure rates, and not every such complaint on file.

The papers lean the other way. Six makers print P2135. GM replaces the sensor cover first; Mercedes-Benz's paper for the 270 engine puts connector contacts first; Ford's one paper is about a chafed harness; Nissan reprograms the computer; Mazda replaces the throttle body on two older models; a scanned Toyota tip lists P2135 among the codes that indicate a possible throttle body concern. In the complaints, 2,643 (83%) describe reduced power, a wrench light or a throttle that did not answer, 945 (30%) a stall, 822 (26%) mention a recall, bulletin, program or coverage notice, and 868 (27%) say the fault came back after a repair or reset.

Is a P2135 limp mode usually a bad throttle body, and should that be the first part you buy? PulsCar sorted 3,414 federal owner complaints, and 3,197 describe reduced power, a stall or no throttle response on the owner's own car. 1,197 of them name a throttle body as the cause or replace it (37%), but 1,239 (39%) never state a diagnosis and only 79 print P2135 at all. The maker papers that print the code point elsewhere first: GM tells dealers to replace the sensor cover before the throttle body, Mercedes-Benz blames contact resistance in connectors, and Nissan fixes a stored P2135 with software when the car drives normally. Read every code, ask for the scan-tool reading of both throttle sensors, and have a dealer run your VIN for coverage before you buy a part. These are owners who wrote to NHTSA, so the shares are not failure rates.

🟢 marks a claim resting on a maker paper in the Sources section; ⚪ marks a shop-price estimate from our guides. Every complaint count comes from the 3,414 complaints we sorted and published; the maker papers are listed.

Words on this page. TP sensor: throttle position sensor; the throttle has two, called 1 and 2, or A and B. DTC: a trouble code such as P2135. VIN: the 17-character number on your registration. PCM, ECM: the engine computer. Flash: a software update for it. StabiliTrak: GM's stability control; its warning can light with a throttle fault. In-service date: the day the car was first sold. Limp mode, reduced power: the computer limits power and speed. Scan tool: a reader that shows live values, not only codes. Relearn: teaching the computer the closed position of a cleaned or new throttle. TSB (bulletin), SSM, program and special coverage: maker notes to dealers (programs also to owners), not safety recalls.

I built PulsCar after a $380 "full diagnostic" in Phuket in 2025 led to roughly $6,000 over six months across several shops (the story is on the About page).

What P2135 says: two throttle sensors that do not agree

The definition. 🟢 GM's bulletins for P2135 give the trigger: "This condition may be caused by the difference between the TP Sensor 1 and TP Sensor 2 exceeding a calibrated value for more than 2 seconds." (12-06-04-003, 11-06-04-007C). Mazda prints "Throttle/Pedal Position Sensor/Switch A / B Voltage Correlation" for the 2009-2010 Tribute (01-007/13) and "Throttle Position Sensor No.1 / No. 2 Voltage Correlation" for the 2003-2004 Mazda6 (01-015/13). Mercedes-Benz prints "P213500 - The values from the position sensors of the throttle valve are implausible relative to each other" for the M177 engine (LI07.10-P-080384). Nissan prints "P2135 - TP SENSOR-B1" (NTB21-080).

What the code is not. It is not proof that a sensor has failed. 🟢 Mercedes-Benz says the entry "could have been caused by occasional transition resistance at contacts" (LI54.18-P-057927), and its M276 and M278 paper blames contaminated contact surfaces between plug pins (LI54.18-P-058597). 🟢 Nissan stores P2135 for a car where "There are no drivability concerns." A code that can come from a contact, a ground, software or the part itself is a reason to test, not to buy.

What you feel. Reduced power with a message or a wrench light, a pedal that does not answer, a stall, sometimes with StabiliTrak warnings on GM cars. Owners describe it coming and going: about 200 complaints say the car was normal after a restart or after switching off.

First: P2135, P2137, P0121, P2111 … which one is yours

Read the exact code before you buy anything, and remember that most owners who wrote to NHTSA did not print a code: about 2,600 of the 3,197 complaints (81%) print none we could find.

The message is not the code. "Service Electronic Throttle Control" can be a throttle fault, and it can be something else that makes the computer cut power. Of the 136 Ram complaints in this set, 57 end at another cause. A scanner that reads the full code list tells you which one you have; a message on the dash does not.

The maker atlas: who prints P2135, and what they blame

Bulletin numbers link to NHTSA's PDF. One fact first: the papers and the complaints barely overlap. Ford, Lincoln and Mercury are 1,579 of the 3,197 complaints (49%) and Jeep, Dodge, Ram and Chrysler another 635 (20%), yet the one Ford paper that lists P2135 covers the 2012-2014 Focus (6 complaints) and no Stellantis paper names the code. Mazda has 8 complaints and Mercedes-Benz 11, yet each prints the code in several papers.

The do-not-replace lines: what the papers tell a shop to hold back

None of these says the throttle body is never the cause; each says that something comes before it.

• GM, P2135: 🟢 "If a vehicle is encountered with this condition, DO NOT replace the throttle body. Instead follow this procedure below." The throttle body is replaced when the scan tool still shows Disagree after the cover: "If TP Sensor 1 and 2 Agree/Disagree parameter displays Disagree, replace the throttle body assembly." Bulletin 007C adds "If DTC P1516, P2101 and/or P2176 are set, replace the throttle body."
• GM special coverage 14582A: 🟢 "Only replace the Hitachi throttle body assembly if the sensor kit does not correct the condition." For Bosch throttle bodies the paper replaces the complete assembly.
• Mercedes-Benz, paper for the 270 engine (version 1; versions 5 and 6 drop P213500): 🟢 "Please do not replace any components!" after the maker's test steps show no component fault.

Which throttle body your GM car has (Hitachi or Bosch) is a part-number question: ask the dealer to check it with your VIN, and for a Mercedes-Benz ask which engine it has. The pattern: for the cars a paper names, a lookup, a contact, a ground, a harness, a sensor cover or software comes before the throttle body. The exceptions are Mazda's two older models, GM's Bosch-built throttle bodies, the Hitachi ones where the kit fails and a Toyota tip that lists P2135 among the codes that indicate a possible throttle body concern.

The 10-minute check

1. Write down the pattern (3 minutes). What did the dash say? How fast were you going? Cold or hot? Did a restart clear it? Steady light or flashing?

2. Read every code, current and history (2 minutes). P2135 alone, or with P2111 or P2112 (the motor), P2138 (the pedal) or P2101? 🟢 GM's coverage 14582A starts with "With a scan tool, verify that DTC P2135, P0121 OR P0221 is set as Current or in History." A parts store reads codes free; the freeze frame and the live values of both throttle sensors need a better scan tool or a shop.

3. Look at the wiring near the throttle body, engine off (2 minutes). 🟢 Ford's Focus paper: "Visually inspect the engine harness for chafing against the intake manifold, near the throttle body." Do not spray contact cleaner (Mercedes-Benz: "Contact spray must never be used on contacts on the engine wiring harness.") and do not wire-brush the plate (Kia: "DO NOT use a wire brush and attempt to remove the coating.").

4. Check the battery terminals (1 minute). A few owners were told a loose battery cable or a failed alternator was behind a throttle warning (our advice: tight, clean terminals first).

5. Run the VIN (2 minutes). At nhtsa.gov/recalls for recalls, and with a dealer for bulletins, programs and updates.

Six situations, and which is yours

"A 2006-2012 Chevrolet, Buick, Pontiac or GMC: Reduced Engine Power, StabiliTrak warning, P2135, P0121 or P0221." GM's papers; coverage is over, and the sensor cover is the first step they print for the bulletin cars and the Hitachi throttle bodies (Bosch ones get the whole assembly under 14582A). → Routes 4 and 1.

"A 2009-2013 Ford Fusion or Escape with a wrench light, or a Focus 2.0L." Ford program 13N03, which owners name (now ended); for a 2012-2014 Focus 2.0L GDI, the harness paper. → Routes 1 and 2, then 5.

"A 2009-2010 Mazda Tribute or 2003-2004 Mazda6 3.0L with P2135." Mazda replaces the throttle body. → Route 5.

"A Mercedes-Benz in limp-home mode, or a BMW or Audi with sporadic throttle faults." Contacts. → Route 2.

"A Nissan with a stored throttle code and a car that drives normally." Software, then a relearn; Honda and Kia print a software update, Kia with a cleaning. → Route 3.

"Power loss on a freezing morning or after rain, then fine." Ice at the throttle plate is printed for the Ram 1500 3.6L and the Kia Carnival, water or ice behind the throttle body for Ford's Ranger and Bronco; none names P2135. → Routes 3 and 2. Any other make: run the VIN and read the full code list. → Routes 1, 2 and 3.

The P2135 price ladder, from the bottom up

How to read the ladder: the ⚪ rows are what our guides carry for a typical shop; the owner rows are what owners wrote to NHTSA, and only cleaning runs clearly above the guide.

How much does it cost to fix a P2135 limp mode, and when does the bill become a throttle body? PulsCar took every dollar figure that owners in the 3,197 complaints tied to a repair or a test for this fault (towing and rental left out): 254 figures in 238 complaints, 160 of them amounts paid or billed. Diagnostic fees run $89 to $500 (median $120), cleaning and relearn figures $45 to $1,059 (median $225) and throttle parts $40 to $4,500 (median $600). Our guides carry $80 to $150 for a shop cleaning and $300 to $800 for an electronic throttle body installed. A software update inside the warranty, or a repair under a program or coverage that covers your VIN, costs $0. So the scan-tool reading of both throttle sensors, the software level and the VIN lookup come before the part, and a second throttle body is a reason to look at the wiring, not to buy a third.

The five routes, cheapest first

Each route is a place the fault can come from, cheapest to rule out first. The throttle body is the most-named end in the complaints (1,197 of 3,197, 37%, named as the cause or replaced; 66% of the 1,816 that name a repair or a cause) but it sits last, because it is the most expensive to get wrong and most papers that name P2135 put a lookup, a contact, a ground, a harness, software or a sensor cover before it. None of these shares is a forecast for your car.

Route 1 · A free repair: recall, special coverage, program or warranty — $0 where your VIN is covered

What it is. The maker has printed a fix for certain cars and pays for it where the VIN is on the list. For P2135 the long-running free programs are over (see the coverage file below; GM's one live throttle body coverage is for a different fault); what is still worth a call is a current recall, a software update inside the warranty, and a goodwill request backed by a printed program number.

What the documents say.

• 🟢 GM special coverage 14582A (October 2015). "With a scan tool, verify that DTC P2135, P0121 OR P0221 is set as Current or in History." Cars are on a VIN list: "It is important to routinely use this tool to verify eligibility because not all similar vehicles may be involved regardless of description or option content." (14582A). The scanned 11273A is the same idea for 2008-2011 V8 trucks and SUVs (printed on the scanned paper).
• 🟢 Ford programs 16B32 and 16B23. "This program will be in effect through September 30, 2017. There is no mileage limit for this program." They replace the throttle body, or reprogram the PCM, for contaminated motor contacts (16B32, 16B23). 16B32 names P2111 and P2112, 16B23 no code; neither names P2135.
• Ford 13N03 (from our guide, not from a paper). 74 owners name it (below), but its paper is not among the files we could read. Our throttle body guide records it as a software update plus throttle body coverage for 2009-2013 Escape, Fusion, Mariner and Milan, now ended.
• 🟢 Nissan recall 26V-081 (2026). Of the recall campaigns we found, one open passenger-car recall names the throttle body itself: 26V-081, certain 2024-2025 Rogue with the 1.5L VC-Turbo. "The gears in the electronic throttle body assembly may break." Dealers reprogram the engine computer and inspect and replace the throttle body as necessary, free of charge, where the VIN is on the recall. It is a gear fault, not a two-sensor disagreement, and none of the recalls we found is a repair for P2135.

What the owners report. 822 of the 3,197 complaints (26%) mention a recall, bulletin, program or coverage notice. The trouble is on the list: of 14 complaints that name GM bulletin 14582 or 11273, 10 say the car was not covered, and 6 of those say the owner was told the VIN or build was not on the list. A 2010 Tahoe owner whose mechanic cleaned the throttle body after P2135 was told the coverage applied "BUT THERE IS NOTHING THEY CAN DO UNTIL THE LIGHT COMES BACK ON." 74 complaints name Ford program 13N03, 37 of them ending at a throttle body; a 2009 Escape owner wrote that the dealer "WILL NOT REPLACE IT UNDER CONSUMER SATISFACTION PROGRAM 13N03 BECAUSE THE COMPUTER READS NO ERROR CODE."

The cheap cause that gets skipped. The lookup, and the code history. The GM coverage tests for the code as current or in history, and Ford's owners were turned away for an empty code list; ask the dealer to read the stored and history codes and to run the VIN for open campaigns before any part is ordered.

Fix it yourself. The lookup only: nhtsa.gov/recalls lists safety recalls by VIN; coverages, programs and updates need the dealer.

At the shop — say this: "Please run my VIN for any recall, special coverage, customer satisfaction program or software update about the throttle body or the throttle position sensors, read the stored and history codes, and write the answer on the repair order before any part is ordered."

Route 2 · Connector, ground and harness — a look first; Ford's chafed-harness repair is 1.3 hours; one dealer quote for a whole engine harness ran to $8,058

What it is. The path the two throttle signals travel: the throttle's connector pins, the engine computer's plugs, the ground points and the harness near the throttle body. A fault here looks exactly like a bad sensor, and it can come and go.

What the documents say.

• 🟢 Mercedes-Benz. "The fault entry could have been caused by occasional transition resistance at contacts." After the maker's test steps, version 6 has the shop check the throttle actuator's contacts, reseat the engine computer plugs F and M, and replace the plug's female contacts only if the fault returns (LI54.18-P-057927); version 1, for the 270 engine, also has the shop clean ground points W11, W9 and W3/2 (version 1). The M177 paper replaces the actuator sockets: "Increased electrical resistance in pins for left and right throttle actuators." (LI07.10-P-080384).
• 🟢 Ford Focus 2.0L GDI. P2135 is one of 17 codes in 18-2062; the repair is a look at the harness near the throttle body and a fix for the chafe, 1.3 hours; the paper lists the repair under the new-vehicle and emissions warranties but says the bulletin does not change their limits, so a 2012-2014 car's own warranty status decides.
• 🟢 Stellantis. A case on a flashing throttle lamp shows that a restart can bring the supply back: "the PCM will turn off the 5-Volt Supply circuit until the next ignition cycle." and sends the shop to the harness routing near a PCM bracket stud (S2408000113). The case is about P0652, not P2135.

What the owners report. 73 complaints (2%) end at wiring or a connector, and 53 of them (73%) say the fault came back. 142 narratives mention a connector, wiring or a harness; 60 of those end at wiring, the rest at another part or with no diagnosis stated. A 2011 Equinox owner: "THEY FOUND THE THROTTLE BODY CONNECTORS WERE NO GOOD AND NEED A NEW WIRING KIT TO FIX." A 2012 Mercedes-Benz E350 owner was told the code was the gas pedal sensor and "IT IS AN ISSUE WITH THE ECU WIRE HARNESS." A 2020 Nissan Kicks owner paid $1,143.69 for a throttle body, saw limp mode return and was quoted $8,057.83 for an engine wire harness.

The cheap cause that gets skipped. The wire, before the second throttle body. At least 6 of the throttle body complaints describe a second or third one, and a 2004 Cadillac CTS owner lists an ECM, a throttle body three times, a gas pedal and a wiring harness, then an engine.

Fix it yourself. A look, not a repair: with the engine off, follow the harness from the throttle body connector for rubbing, melted insulation or a loose plug; do not spray contact cleaner.

At the shop — say this: "Before another throttle body: show me the voltage of both throttle sensors on the scan tool, inspect the harness, the connector and the ground points, and tell me whether a harness paper for my model applies."

Route 3 · Cleaning, relearn and software — $15 yourself, $80 to $150 at a shop, $0 under a warranty

What it is. Carbon or ice on the throttle plate, water behind it, a throttle whose closed position the computer has not learned, or software that misreads the signals. 73 complaints (2%) end at a cleaning or relearn alone; about 120 in all mention a cleaning.

What the documents say.

• 🟢 Relearn. GM's P2135 procedure ends with "Perform the Throttle Learn Reset Procedure." (12-06-04-003). GM's carbon bulletin for V8 trucks and cars explains why: "As carbon builds up in the throttle body of a high mileage vehicle, the ECM/PCM learns to compensate by increasing the throttle plate angle." It lists P0121 and P2176 among its codes, not P2135 (PIP4578B).
• 🟢 Software and relearn. Nissan's 2020-2021 Frontier bulletin (P0223, P0507, P2135, no drivability concern): "When reprogramming is complete, you will be required to perform Throttle Valve Closed Position, Idle Air Volume Learning, Accelerator Closed Position and DTC Erase." (NTB21-080).
• 🟢 Cleaning with a rule. Kia's 2019-2020 Forte bulletin (codes P0101, P0106, P0068, not P2135) cleans the throttle inlet wall after the ECM update and warns "DO NOT use a wire brush and attempt to remove the coating." (FUE047).
• 🟢 Ice and water. Ram 1500 3.6L: "CAUSE: Throttle body blade icing up." (09-023-23). Kia's Carnival bulletin says the plate may freeze after a cold soak (FUE 062). Ford's Ranger and Bronco message: "This may be due to water or ice buildup in the intake manifold behind the throttle body." (SSM 50203). None of the three names P2135.

What the owners report. 53 of the 73 who ended here (73%) say the fault came back. A 2010 Avenger owner: "CLEANED THROTTLE BODY AND PROBLEM WENT AWAY UNTIL THREE MILES DOWN THE ROAD WHEN IT RETURNED--THIS TIME ACCELERATOR WORKED UNTIL 30 MPH." Of the 1,197 that end at the throttle body, about 30 mention a cleaning, and 21 of those say the fault returned. Only 10 complaints use the word relearn (or re-learn).

The cheap cause that gets skipped. The relearn and the software level. A cleaned or new throttle changes the closed position and idle airflow the computer expects; a cleaning without the learn is half a repair on the cars whose papers print it.

Fix it yourself. Where the engine allows it a cleaning is a driveway job and a can costs about $15 in our throttle body guide. The honest limits: do not wire-brush the plate, and clean only the way the maker's procedure for your engine says; expect to need a scan tool for the relearn on GM V8s and Nissans.

At the shop — say this: "Is the engine computer on the latest software for my VIN, and if you clean or replace the throttle, will you run the throttle learn and write down the sensor readings before and after?"

Route 4 · The throttle position sensor or its cover alone — on GM cars and trucks 1.2 to 1.7 hours of labor plus the cover; owners reported a median of $500

What it is. On the GM engines in these papers the two position sensors sit in a cover that is sold apart from the throttle body, and GM's P2135 bulletins replace it first (14582A replaces the whole assembly on Bosch-built throttle bodies). 132 complaints (4%) end at a sensor or cover without a new throttle body.

What the documents say.

• 🟢 GM. The covers are in 12-06-04-003 and 11-06-04-007C. The shop cleans the bore, fits the cover and a new gasket, clears the code and watches the scan tool while the pedal moves: "If TP Sensor 1 and 2 Agree/Disagree parameter displays Disagree, replace the throttle body assembly." Special coverage 14582A applies the same kit to Hitachi throttle bodies.

What the owners report. Throttle bodies named or replaced outnumber sensors or covers named or replaced nine to one: 1,197 against 132. By make the gap is not the same: Chevrolet has 38 complaints that end at a sensor or cover among its 410 (9%) and Ford 25 among 1,480 (2%). 54 of the 132 (41%) say the fault came back, against 27% of the complaints that end at a throttle body. A 2011 Edge owner: "THEY REPLACE THE THROTTLE BODY SENSOR AND CHECK ENGINE LIGHT WAS GONE, BUT A FEW HOURS LATER IT CAME BACK ON AND IT STALLED ON ME AGAIN."

The cheap cause that gets skipped. Asking whether the sensor is sold alone. On the GM cars in the papers it is a cover with its own part number; Ford's 16B23 and Mazda's papers replace the whole throttle body, and our throttle body guide records Toyota quotes of $1,000 to $1,400 where the sensor is not sold separately.

Fix it yourself. Not without a scan tool. GM's procedure takes the throttle body off the engine, cleans it, fits a cover and a new gasket and ends with the learn reset on a scan tool, so the cover is a shop job unless you have the tool.

At the shop — say this: "Is there a sensor cover or kit for my throttle body that is sold separately, and can you show me the Agree or Disagree reading of the two sensors before and after it is fitted?"

Route 5 · The throttle body, and the computer as a last resort — $300 to $800 installed in our guide; owner figures median $600

What it is. The whole assembly (the plate, its motor and both sensors), or at the very end the engine computer. 1,197 complaints (37%) end at a throttle body named as the cause or replaced and 62 (2%) at the computer.

What the documents say.

• 🟢 Mazda. For the 2009-2010 Tribute built between 22 June and 15 October 2009, P2135: "This concern may be attributed to the Throttle Body Assembly hardware." and 0.6 hours (01-007/13). For the 2003-2004 Mazda6 3.0L the paper replaces the throttle body with part AJT1-13-640 and then adds a diode to the harness (01-015/13).
• 🟢 GM. The throttle body is replaced when the two sensors still disagree after the cover, when P1516, P2101 and/or P2176 are set, and on Bosch-built throttle bodies in coverage 14582A.
• 🟢 The computer. GM's paper for P2101 or P1516 on the 2019 XT4 (2.0L) and the 2.7L Silverado 1500 and Sierra 1500 says "If the published diagnostics lead to ECM replacement and the vehicle was built prior to February 2019 do not replace the ECM." and puts a terminal-tension and wiring check before the throttle body (PIP5660). Toyota's T-SB-0005-24 replaces the ECM together with the fuel pump (T-SB-0005-24). Neither paper is about P2135.

What the owners report. 325 of the 1,197 (27%) say the fault came back after a repair or visit, and 44 of the 62 who ended at the computer (71%). Ford is 776 of the 1,197 throttle body complaints, Chevrolet 136 and Jeep 70. Among GM cars the shares differ: 23 of 37 Traverse complaints (62%) and 21 of 43 Equinox (49%) end at a throttle body, against 35 of 120 Malibu (29%) and 18 of 79 Impala (23%), whose owners also name pedals and sensor covers. The Traverse is the outlier on stalls (1 of 37 against 30% overall): owners describe a loss of speed and StabiliTrak warnings instead.

The cheap cause that gets skipped. The wiring and the coverage, again, and the relearn after the part. A new throttle body on a car with a harness fault can bring the trouble back: Mazda's diode paper (electrical noise in the engine harness after a new throttle body) and a 2020 Nissan Kicks owner, whose dealer quoted an engine harness after a paid throttle body, point the same way.

Fix it yourself. Our throttle body replacement cost guide says that on many four-cylinder engines the throttle body is four bolts, a gasket and a connector, and carries the prices and the relearn. Do not skip the relearn (our advice). A computer is not a driveway job.

At the shop — say this: "Before a throttle body: did the two sensors disagree on the scan tool, did you check the harness and ground, and is the part and the relearn covered by any warranty or program on my VIN? If it fails again, what do you check next?"

The coverage file: which repairs may be covered, as of September 2026

The status is our computation from the printed terms, as of September 2026, not a promise from any maker. Most papers print no end date; the VIN decides. A bulletin by itself is not coverage.

Programs and updates are not in the safety-recall lookup, so the dealer is the lookup. None of the recalls we found is a repair for P2135; the nearest is Nissan's 14V-583 for certain 2013-2015 Infiniti M35, Q50 and Q70 hybrids, where a software error can let the throttle reopen after the signal from one of the two throttle position sensors is lost and restored, which Nissan says may cause unexpected acceleration and increase the risk of a crash; dealers reprogram the computer. Of the recalls we found, the Rogue gear recall above is the one open passenger-car recall that names the throttle body itself; a Motiv recall (25V-137) for a loosening throttle position sensor connector pin covers certain electric truck chassis, where Motiv says a loss of drive power increases the risk of a crash.

What 3,197 complaints show

We sorted 3,414 federal owner complaints by written rules (the sorting rules, how we did it): 3,197 describe a throttle position-signal or reduced-power event on the owner's own car; 217 do not. Only 79 of the 3,197 print P2135, so every count below is "complaints describing this fault", not "P2135 complaints".

What the owners describe. 2,643 (83%) state reduced power, a wrench or power message, or a throttle that did not answer; 945 (30%) a stall or a loss of drive; 822 (26%) mention a recall, bulletin, program or coverage notice; 868 (27%) say the fault came back after a repair or reset. Of the 1,329 that name either a throttle body or a sensor, 90% name the throttle body. The split follows the parts each maker sells: GM sells a sensor cover (9% of Chevrolet complaints end at a sensor or cover), while Ford's 16B23 and Mazda's papers replace the whole throttle body (2% of Ford's).

Who files. Ford is 1,480 of the 3,197 (46%) and, with Lincoln and Mercury, 1,579 (49%); then Chevrolet (410), Jeep (278), Dodge (143), Ram (136), GMC (79) and Chrysler (78), in 54 makes. The median model year is 2012 and, of the 2,494 that give a mileage, the median is 70,000 miles. 1,207 (38%) were received in 2015 and 2016, which tells when owners filed, not when cars failed.

Can a P2135 limp mode be a harmless glitch, and how often does it end at the throttle body? PulsCar counted what 3,197 federal owner complaints say. 2,643 (83%) describe reduced power or a throttle that did not answer, 945 (30%) a stall and 868 (27%) say it came back after a repair; 1,197 (37%) name a throttle body as the cause or replace it, 132 (4%) a sensor or cover and 1,239 (39%) never state a diagnosis. About 200 say a restart made the car normal again, which is how a harmless glitch looks and also how an intermittent wiring or sensor fault looks. Only 79 print P2135, and no maker paper we read tells an owner to stop driving, so our tow rules for a car that drops into reduced power, stalls or has a flashing check engine light are stricter than any of them. These are owners who wrote to NHTSA, so the shares are not failure rates.

The complaints that print P2135 themselves

79 of the 3,197 print P2135 (2%): 73 on cars, trucks and SUVs, 4 on Harley-Davidson motorcycles, 1 on a Yamaha and 1 on a van conversion. Chevrolet is 44 of them (Malibu 14), Ford 8, GMC 4 and Hyundai 4; 56 are model years 2008 to 2012, which fits the GM papers. 43 end with no diagnosis stated, 17 at a throttle body, 5 at a sensor or cover, 4 at wiring, 4 checked and cleared, 3 at another cause, 2 at a pedal and 1 at a cleaning. 66 describe reduced power (84%), 14 a stall and 25 say the fault came back. A 2011 Malibu owner with P2176 and P2135 stored was told a new battery and cables ($733) were the fix and that the throttle had to be relearned after the battery was out; the owner disputes that the battery had been out too long.

When the car loses power on the road: the safety side

Of the 945 stall complaints, 577 also state reduced power. About a third (343) mention a highway, freeway, interstate or expressway and about 150 say it came without warning; across all 3,197, 66 describe a speed falling or limited to under 40 mph, for example "LUCKILY I WAS NOT ON THE HIGHWAY AT THE TIME AS GOING FROM 65 TO 20 WOULD HAVE BEEN VERY DANGEROUS." In NHTSA's own fields, 21 of the 3,197 are marked as a crash, 14 with an injury and 80 as towed (some of those narratives describe another failure); none in this set is marked with a death, but the pedal-side set on the P2138 page holds one, a 2016 Malibu that lost power at highway speed in 2025. A 2016 Fusion owner wrote of a daughter on a highway ramp: "UPON ENTERING THE HIGHWAY AND ACCELERATING ON THE RAMP THE VEHICLE STALLED AND BECAME UNRESPONSIVE TO ACCELERATION WHILE PRESSING DOWN IN THE PEDAL."

Ford's letter for contaminated throttle motor contacts (P2111 and P2112) describes the fallback this way: "In this mode, while engine power and vehicle speed are reduced, the power steering, power braking, lighting, and climate control systems remain fully functional." (16B32). Some owners say otherwise: a word search finds about 110 complaints that mention lost, heavy or failed steering or brakes; we estimate at least 70 really describe it, and the rest are unrelated mentions or say it did not fail. Nissan's Rogue recall states the risk plainly: "Broken throttle body gears can cause a loss of drive power, increasing the risk of a crash." If the car drops into reduced power, will not accelerate, stalls or the check engine light is flashing, follow the tow rules at the top of this page (our advice).

What owners say they paid

254 figures in 238 of the 3,197 complaints are ones an owner tied to a repair or test for this fault: 79 amounts paid, 81 bills, 92 quotes and 2 offers. They are what owners wrote, not audited invoices; we publish them with NHTSA complaint numbers and list the 205 we left out with reasons (towing, rental, a loan balance, trade-in or vehicle value, work on other systems). The overall median is $595.50; the 160 amounts paid or billed give $550 and the 92 quotes $600, so quotes run about $50 above bills. For throttle parts (185 figures) the middle half runs $400 to $800. The 164 figures in complaints that end at a throttle body give a median of $600 and the 11 that end at a sensor or cover $500.

Why the fault comes back after a repair

A lower share does not prove a repair lasts longer; the table shows which repairs owners complained about afterwards, not which one to choose.

The part was not the problem. A throttle body fitted over a harness or contact fault can bring the trouble back with a new part; Mercedes-Benz, Ford and Mazda print wiring and contact work. The relearn may have been skipped. GM's bulletin ends with a learn reset and Nissan's with three learns. The software did not hold, or was never the cause: 44 of the 62 who ended at the computer say the fault came back. It was intermittent and nothing was found: 37 of the 142 that were checked and cleared say it came back. The coverage was refused: 10 of the 14 who name GM 14582 or 11273 say the car was not covered; 6 say they were told their VIN or build was not on the list. The high shares for cleaning, wiring and computer work come from people who describe a repair attempt; the 1,239 with no diagnosis stated mostly describe no repair at all; 181 of them (15%) still say a shop visit or a part they do not name did not stop the fault.

Can you drive with P2135?

It depends on how the car behaves, and this is our rule, not any maker's: no maker paper we read tells an owner to stop driving or tow the car for P2135 or the throttle faults around it. The only maker note we read that has dealers tell owners to restart and keep driving is Ford's message for a different code, P2101, on 2022-2023 F-150, 2023 Expedition and 2023 Navigator vehicles with the 3.5L engine built on or after 1 October 2022 (SSM 51827). Our advice is stricter than every paper.

A steady light on a car that has not lost power and drives normally: a shop visit within days; avoid highways and heavy traffic until then (our advice). If the car drops into reduced power, will not accelerate or stalls: switch on the hazard lights, move out of the traffic lane as soon as it is safe, stop in a safe place and have the car towed; do not drive it on to the shop, even if a restart cleared it (our advice). If the check engine light is flashing: pull over safely, switch the engine off and have the car towed; the only exception, for a flashing light alone on a car that starts and runs normally, is a shop within 2 to 3 miles, reached gently, under 40 mph with light throttle; never for a car that will not start (our advice). A restart that makes the car normal again is not a repair; the fault can return at any time.

Should you buy a used car with a P2135 history?

Ask what was found, not what was replaced: 325 of the 1,197 complaints that end at a throttle body say the fault came back, and 53 of the 73 that ended at a cleaning. Ask for the invoice that names the test (the two-sensor reading, the harness check, the software level, the relearn), and have a dealer run the VIN for open recalls and programs. Before you pay, drive the car through a full warm-up and have it scanned for history codes and the live readings of both throttle sensors.

Clearing P2135 before an inspection

A cleared code returns if the cause is still there, and many inspections need the car's self-checks to have run again, so ask the station how many trips it needs; how to reset a check engine light covers the mechanics. Do not clear a code before a dealer has read it: GM's coverage 14582A tests for P2135, P0121 or P0221 as "Current or in History", and a 2009 Escape owner was refused Ford's program 13N03 because "THE COMPUTER READS NO ERROR CODE."

What the papers tell a shop to do with P2135, checkpoint by checkpoint

1. Confirm the code and the build. GM: verify the code as current or in history; Mazda and Ford: check the build date, and Mazda's Tribute paper replaces only when P2135 is present.
2. Do the maker's test steps first. Mercedes-Benz asks for all stored test steps before any contact work.
3. Read both sensors against each other. GM's line "TP Sensor 1 and 2 Agree/Disagree" is the test.
4. Look at the harness and the ground. Ford's chafe check, Mercedes-Benz's ground points (engine 270, version 1 only), Mazda's diode harness.
5. Check the software level. Nissan: confirm the ECM part number before flashing; GM 007C: an engine computer update on every vehicle it covers.
6. Replace the narrowest part the paper allows: GM's cover before the assembly on Hitachi-built throttle bodies, Mercedes-Benz's plug contacts before the unit; Mazda's Tribute paper and GM's Bosch-built throttle bodies replace the assembly.
7. Relearn and write it down. GM and Nissan print the relearn; Nissan wants the ECM part numbers before and after on the repair order (our advice: also the sensor readings and the VIN lookup).

Three P2135 traps

Trap 1 · Buying a throttle body from the dash message. 1,197 of the 3,197 complaints end at a throttle body and 1,239 never state a diagnosis; GM's two P2135 bulletins (12-06-04-003, 11-06-04-007C) say not to replace it before the sensor cover, and Mercedes-Benz's paper for the 270 engine says not to replace any component once its test steps find none faulty. Ask for the readings first.

Trap 2 · Restarting and carrying on. About 200 complaints say a restart made the car normal again; separately, 868 say it came back after a repair, and 945 describe a stall. A restart that works once tells you nothing about the next time on the highway. If the car drops into reduced power, will not accelerate or stalls, follow the tow rule in the triage box, even if a restart cleared it (our advice).

Trap 3 · Waiting for the light, or clearing it. A 2010 Tahoe owner was told the coverage applied "BUT THERE IS NOTHING THEY CAN DO UNTIL THE LIGHT COMES BACK ON." Do not clear the code; note the date, speed and message every time it happens.

Three composite scenarios

These are composite scenarios, not individual customers; the figures come from this article. A 2010 GM SUV drops into reduced power on a highway ramp with P2135 stored: the owner stops safely, has it towed, and asks for the Agree or Disagree reading and the VIN lookup before a part; the coverage papers are over, so the sensor cover (1.3 hours of labor in GM's paper) comes before a throttle body at $300 to $800. A 2011 Fusion went into limp mode twice and the dealer finds no code: the owner keeps the dates and asks for the history codes and the harness check before another part, and has it towed if it drops into reduced power again. A 2021 Frontier shows the engine light with P2135 and drives normally: the owner asks whether the ECM part number matches Nissan's bulletin; the fix is a reprogram and three learns, $0 if a warranty covers it.

The P2135 plan: 10 minutes, today, this week

Today, 10 minutes: write down what the dash said, your speed and whether a restart cleared it; have a parts store read the codes (ask for stored and history codes, and do not let them clear anything); with the engine off, look at the wiring near the throttle body. Today, by phone: ask a dealer to run your VIN for recalls, coverage, programs and software updates. This week: pay for one diagnosis with the live readings of both throttle sensors, the software level and the harness check, and ask for the relearn after any part. If the car drops into reduced power, will not accelerate, stalls or the check engine light is flashing, follow the two tow rules in the triage box (our advice).

What this page cannot tell you

The complaint file holds only cases where an owner wrote to NHTSA, in the owner's words, with nothing verified; owners whose trouble ended are mostly not in it. Only 79 of the 3,197 print P2135, so most were found by the owner's words, not by the code. Our search did not reach every such complaint: we think roughly 1,000 to 1,500 more exist, mostly worded around P2111 and P2112, "Service Electronic Throttle" and a throttle body for a stall, so every share on this page describes the complaints we sorted. A few counts marked "about" come from searching the owners' words and are rough. 39% state no diagnosis, so the true split between a throttle body, a sensor, wiring and software is unknown. Counts are of complaints, not cars; nothing here is a failure rate. Five papers on NHTSA's list have no file to read, among them Ford's 13N03. Prices are rounded from our guides and from what owners reported; they are not quotes.

Sources and documents

Primary documents only. Claims marked 🟢 rest on one of the items below; claims marked ⚪ are shop-price estimates carried from PulsCar's repair guides. Links checked October 2026; dates are given in the text where the paper prints one.

1. General Motors: 12-06-04-003, 11-06-04-007C, 11273A (scanned), 14582A, PIP4578B, PIP5660, N242445290.
2. Mazda: 01-007/13, 01-015/13, 01-015/13A.
3. Mercedes-Benz: LI07.10-P-080384, LI54.18-P-057927 version 1, LI54.18-P-058597, LI54.18-P-057927 version 6.
4. Ford: 18-2062, 16B32, 16B23, SSM 50203, SSM 51827.
5. Nissan, Honda, Toyota, Kia: Nissan NTB21-080, Nissan NTB23-021, Honda 14-052, Toyota T-TT-0321-15 (scanned), Kia FUE047, Kia FUE 062, Toyota T-SB-0005-24.
6. Stellantis (Chrysler, Dodge, Jeep, Ram): 18-032-16, S2408000116, S2408000113, 09-023-23.
7. BMW and Audi: BMW SI B12 26 09, Audi 2018260/7.
8. NHTSA recalls: 26V-081 (Nissan Rogue), 14V-583 (Infiniti hybrids), 25V-137 (Motiv).

Data and sorting: complaints, amounts, figures left out, documents, the sorting rules and how we did it (CC BY 4.0).

Price guides: throttle body replacement, a car that will not accelerate and diagnostics. Related: the pedal pair, P2138, a car that stalls while driving, hesitation when accelerating and the check engine light.

For a limp mode the evidence is the code list with its history, the live readings of both throttle sensors, the software level and the harness check; a code read alone is not a diagnosis.

Prices verified July to October 2026 in the repair guides they are carried from and in the owner reports above, and reviewed quarterly. Technical documents verified October 2026.

Did P2135 clear with a cover, a harness repair, software or a program? Email [email protected] with the vehicle, mileage and outcome.