SORTING RULES - THROTTLE POSITION SENSOR "A"/"B" VOLTAGE CORRELATION (P2135) AND THROTTLE POSITION / THROTTLE BODY / ELECTRONIC THROTTLE FAULTS WITH REDUCED POWER (SISTER CODES P2136 AND P2137) PulsCar analysis of NHTSA public data, October 2026. License: CC BY 4.0 Fingerprint of the rules text below, taken when it was written and before any complaint was sorted: 04fbf84a73e8ba3fab8f94f5e4b4e4d9a85c59cb5602d040e28219a5cd555aec (2026-10-30T16:14:53Z) [Changed when published, wording only, so that the file reads on its own: the title line moved up; one phrase about what the sorting records reworded; one word in the description of category C replaced by "reprogramming". No rule changed.] Written before any complaint in the set was sorted. ## Pool (how the complaints were found) NHTSA complaints received 2015-01-01 to 2026-10-04 (782,908 narratives; 2026-10-04 is the latest received date in the flat files). A complaint is in the pool if its narrative matches any of the following case-insensitive text searches (R2 and R3 also need one of their context words somewhere in the same narrative): 1. R1 - the code P2135 by any spelling (letter O for zero, a space, hyphen or period after the P, suffix 00), or the bare number after a code word: `(? U. - R2 a part named as the cause by a shop, dealer or mechanic, or replaced/cleaned, is the category even if the owner says the problem later came back (returned = yes); if a different cause is named later, that one. A tentative "may need / might be / suggested we look at" is not naming -> U. - R3 throttle body AND its sensor replaced together = B; sensor or sensor cover alone = S; throttle body replaced and cleaned = B; cleaned or relearned only = L; cleaned then replaced = the last repair (B or S). - R4 a recall, special-coverage or customer-program letter that names a throttle body (or sensor) replacement as the repair counts as naming it: B (or S), recall = yes. An "update" or "fix" with no named action -> U. - R5 sudden unintended acceleration, surge, stuck pedal or high-rpm event with no throttle-sensor fault, code or reduced-power event stated -> N. - R6 a shop's suggestion of a throttle service or cleaning that was not done, with no cause found -> U; power loss explained by another system found by the shop -> O. - R7 a shop that names a different cause (injectors, transmission, battery, ignition, a different sensor) -> O, even if the owner doubts it. - R8 dealer found nothing, could not duplicate, or only reset/cleared -> K; if the dealer then names a suspect part but does nothing yet -> U. - R9 returned = yes only when the narrative says the same problem came back after a repair, reset, shop visit or program, or that the repair did not fix it; recurrence before any repair -> no. - R10 stall = yes when the narrative says the engine stalled, shut off, died or lost drive; limp = yes for a reduced-power message or limp mode, loss of power, no acceleration or a throttle that does not respond. - R11 recall = yes only when a specific recall, program, TSB or coverage is performed, offered, seen, named, asked about or reported missing; a general remark that the maker should recall -> no. - R12 where the excerpt does not settle it, take the narrower reading (flag no; category U). - R13 a passing remark that no recall exists (nobody checked, asked or offered one) -> recall no; a dealer/maker check, a missing letter or a named program -> yes. - R14 where the notes of both sortings state a fact (e.g. a replacement) from the cut-off tail of a long narrative, accept it. - R15 a TPS or throttle body that is only one item in a shotgun list of replaced parts, with no stated link to a throttle fault, code or reduced-power event -> N (all flags no). - R16 a part replaced anywhere in the narrative outranks a cleaning: L only when nothing was replaced (replace-then-clean takes the replaced part's category). - R17 'dealer fixed / repaired the problem' or 'got it fixed' with no named part or action -> U. - R18 a shop/dealer person's guess from symptoms ("seems to think", "gotta be", "thought", "possibly", "told it is" without naming who) -> U; a definite "diagnosed / said it was / needs replacing" -> named. - R19 a throttle body or sensor replaced by anyone (owner included) counts as B/S even if it did not fix the problem, unless a later different cause is named (R2 restated). - R20 stall = yes only when the narrative says stalled, shut off, died, shut down; "lost power" alone is limp = yes, stall = no. - R21 a throttle lag/surge complaint with no throttle sensor code, wrench/reduced-power event, and an owner-stated non-throttle cause -> N. - R30 'known problem' said by the owner or dealer alone, with no notice, campaign or missing notification mentioned -> recall no; the dealer/maker said it is known/aware and the owner was never notified (missing known-issue notice) -> recall yes. - R31 a parts-store, code-reader, forum or outside-mechanic "believe/think" cause is U (R1+R18); a part replaced by anyone counts (R19) even if it did not fix. - R32 a throttle body (or sensor) listed among several parts for an event that is only surge/sudden acceleration/rough running with no throttle fault, code or reduced-power event stated -> N, all flags no (R5+R15+R21). - R33 throttle body replaced together with its own TPS = B; with wiring/connector also replaced the W/S/B/P/C order puts W first. - R34 recurrence of the symptom before any repair is returned no; a bare "problem after the repair" with a different symptom is returned no (R12). - R35 a code readout whose label contains a sensor name ("code P2135 = TPS", "P2138 throttle position sensor") with no statement that the part failed, needs replacing or was replaced -> U; a dealer/mechanic saying the part is bad, or the part replaced -> the part's category. - R36 a vague delay/lag in throttle response (no code, no wrench, no reduced-power message, no stated sensor) -> limp no; with no throttle sensor wording at all -> N. - R37 a general complaint that the maker should have recalled it, or "no recall exists", is recall no (R11+R13); a named software update/TSB seen only in articles about other cases is recall no. - R38 if the symptom came back after a shop visit (service, clear, reflash, diagnostic) even without a part, returned yes (R9); if the narrative gives only a count of occurrences with no repair between, returned no. - R39 an engine/truck fire that follows a throttle warning, with no shop or dealer naming a cause -> U (the fire is not a named cause; the owner's sighting is R1). - R40 stall = yes for 'stalled / stalling / died / shut down / cut off'; 'attempt to stall', 'chugging', 'shuddering', 'lost power' or 'coasted' alone -> no (R20 restated). - R41 two throttle parts named as the cause together by a shop (throttle body AND its sensor) = B (R3); a dealer who explains the behaviour as normal or as the computer's design, with no fault and no repair -> K. - R50 a recall/program/TSB that was performed counts for recall=yes when the narrative presents it as part of handling this problem (attempted fix or blamed cause); an incidental recall for an unrelated item -> no. - R51 'TPS' (or similar) that is clearly tire pressure / a false match with no throttle fault named -> N, all flags no. - R52 a wrench light or 'reduced power' message stated for the event = limp yes; an ETC/lightning-bolt light alone, or a stall alone, is not limp. - R53 dealer declines or cannot diagnose because the light is off, with no test or inspection described -> U (K needs a test/inspection, 'could not duplicate' or found-nothing). - R54 a flag describing an event that has another stated cause (e.g. seized engine) with only an incidental throttle code -> no. - R55 mechanical cable-operated throttle part failures (motorcycle cam, pulley) are not an electronic throttle position-signal fault -> N, all flags no. - R56 throttle feel / lag / lurch / jerky pedal with no sensor, code, wrench or reduced-power/no-response statement -> N. - R57 an independent shop (not a parts store or the owner's reader) that reads the code and says throttle body -> named: B. - R58 failure of a part replaced years earlier, with no statement that the same problem came back -> returned no. - R59 a sensor the narrative places in the gas pedal is P even when the owner calls it TPS. - R60 many unrelated parts/modules replaced and the shop never found the cause -> U. - R61 an owner's own battery disconnect or key-cycle reset to clear limp mode is not a repair -> U (not L). - R62 dealer attributes the event to icing, oil or condensation in the throttle body and does nothing -> U. - R63 returned = yes only after an actual repair, part change, reset, reflash or program; a diagnosis-only visit followed by more events is recurrence before repair -> no. - R64 throttle cleaning together with a computer reflash = L (the throttle-specific action ranks above C). - R65 a control module (throttle body control module, TAC module) named as the cause by a shop, not yet repaired = C. - R66 an owner's genuine question 'is this a recall item?' = asked about -> recall yes; 'should be recalled / needs a recall' is a general remark -> no. - R70 a named shop/dealer visit where nobody could find a cause (no codes, nothing found) -> K; "no idea what is causing it" with codes present, or no shop stated -> U. - R71 an ETC / "service electronic throttle" light or message alone is not a reduced-power statement; limp = yes only if reduced power, slow, no acceleration or no response is stated. - R72 a throttle actuator control (TAC) unit replaced = the throttle body (B). ============================================================================== RULE OF THE CONSISTENCY CHECK (the resolution column says "changed in consistency pass" and rule_applied starts with Rcons1 for the complaints it changed). Rcons1: 79 complaints on which both sortings gave the same answer, but whose notes used hedging words ("suspects", "suggested", "believes", "thinks", "possibly", "likely"), were read again against the written rules on guesses and named causes (R1, R2, R18, R19, R31, R35) and on not-relevant cases (R5, R15, R21, R32). Where the agreed answer clearly broke a rule it was changed under that rule: 17 changed (14 to "no diagnosis or repair stated"; 3 changed a recall mark only). The number in brackets after Rcons1 in rule_applied is the settling rule above that was applied. ============================================================================== POOL HISTORY - First search: 2,514 complaints, found by the four text searches written out in the pool section above (R1 the code P2135: 78; R1b the sister codes P2136 and P2137: 1; R2 the throttle position sensor in the owner's words with a fault or symptom word: 545; R3 the throttle body, electronic throttle or throttle actuator with a reduced-power or no-response word: 1,989; 87 complaints matched more than one search; 35 matched only R1, 474 only R2, 1,918 only R3; the one R1b complaint also matched R2 and R3). Nothing was sampled: every complaint the searches returned was sorted. They were sorted in 11 groups of about 230. - Left out on purpose: narratives that describe sudden unintended acceleration, a stuck-open throttle or a pedal that feels wrong without a throttle-sensor fault, a code or a reduced-power event; the accelerator pedal sensor pair (P2138) has its own page and is counted here only when the complaint describes a reduced-power event (category P). - Independent check (a separate search of the whole complaint file, run after the first batch was sorted): about 780,000 narratives that the first search had not returned were searched again with other wording and about 1,500 of them were read against the same relevance rule; 900 were added. They use these wordings: a "Service Electronic Throttle" or "Service Throttle Body" message with stalling, shutting off or lost power; a throttle body diagnosed or replaced for stalling, hesitation, surging or failing to accelerate; "engine power is reduced" (the words in another order) with a throttle body or sensor; the accelerator pedal position sensor ("gas pedal sensor", "APP", the codes P2122-P2138) with reduced power; "throttle unresponsive", "lost all throttle", drive-by-wire; the ETC or lightning-bolt warning light; and throttle actuator codes (P2101, P2104, P2106, P2110, P2111, P2112, P2118, P2119, P0121-P0123) with a stall or loss of power. One further complaint printed the code with two extra digits glued on (P213577). The check stopped at its row cap of 900: it had judged 978 complaints to be misses, wrote 900 and left 78 (throttle body replaced or diagnosed with a stall) unwritten, and estimated that roughly 1,000 to 1,500 further relevant narratives, mostly "Service Electronic Throttle" or ETC-light wording, throttle-actuator-code wording such as P2111 and P2112, and throttle-body-for-stalling wording, were not reviewed at all. None of those were sorted and none are counted anywhere in this study. All 900 that were written were sorted twice under exactly the same rules (second batch, 4 groups of 225). found_by in the complaints file says which search found each complaint ("first search" or "independent check"). - Final: 3,414 complaints; 3,197 relevant, 217 not relevant. A relevant complaint is one that describes, on the owner's vehicle, a throttle position-signal or reduced-power event: it names P2135, P2136 or P2137; or it describes the throttle body, throttle actuator, electronic throttle or throttle position sensor as failed, replaced, cleaned, blamed or diagnosed as the cause of reduced power, no throttle response, stalling, a wrench or engine light or a code; or it describes such a symptom together with a throttle or pedal sensor code or wording, even if the cause is unknown. All shares in this study describe the sorted set.