PULSCAR ANALYSIS - SORTING RULES FOR SECONDARY AIR INJECTION COMPLAINTS (P0410 STUDY)
PulsCar analysis of NHTSA public data, October 2026. License: CC BY 4.0

The rules below were written and fingerprinted before any complaint was sorted. Fingerprint line (date UTC, checksum, file): 2026-10-21T14:01:25Z e766b64411ccdd9601babea3c8b7a547967d7f1af5c71003362c0b2f01aef8c5  codebook.md


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
(the third also needs one of its context words somewhere in the same narrative):

1. R1 - the code P0410 by any spelling (letter O for zero, a space, hyphen or period after the P, suffix 00), or a bare number after a code word:
   `(?<![A-Z0-9])P\s?[-.]?\s?[0O]\s?4\s?1\s?0(?:\s?[-:]?\s?[0O]{2})?(?![0-9])`
   `\b(?:code|codes|dtc|dtcs|error|cel|coded|fault)\W{0,6}#?\s?[0O]?410\b`
2. R1s - a sister code of the secondary air family (P0411 to P0419, P0491, P0492, P2430 to P2449), same spellings:
   `(?<![A-Z0-9])P\s?[-.]?\s?(?:[0O]\s?4\s?1\s?[1-9]|[0O]\s?4\s?9\s?[12]|2\s?4\s?3\s?[0-9]|2\s?4\s?4\s?[0-9])(?:\s?[-:]?\s?[0O]{2})?(?![0-9])`
   `\b(?:code|codes|dtc|dtcs|error|cel|coded|fault)\W{0,6}#?\s?(?:[0O]?41[1-9]|[0O]?49[12]|24[34][0-9])\b`
3. R2 - the secondary air injection system in owners' words (secondary air, air injection, air pump, smog pump, air switching valve, SAI pump or valve):
   `secondary\s*air|air\s*injection|air\s*injector|smog\s*pump|\bair\s*pump|air\s*switching\s*valve|\bair\s*switch\s*valve|\bsai\s*(?:pump|valve|system|code)|\bsai\b[^.]{0,30}\b(?:pump|valve|relay)|\bair\s*assist\s*(?:pump|valve)|\bpulse\s*air|\bvsv\b[^.]{0,30}\bair`
   together with: `check\s+engine|engine\s+light|\bcel\b|\bmil\b|\bcode|\bdtc|stall|limp|reduced\s+power|emission|fail|replac|bad|faulty|defect|malfunction|diagnos|service\s+engine|warning|recall|noise|loud|whin|buzz|smell|burn|fire|melt|relay|fuse`

Background for the reader (not a sorting rule): the secondary air injection system blows fresh air into the exhaust
for the first minute or so after a cold start, so the catalytic converter lights off sooner and the engine's
emissions are lower. It is built from an electric air pump, one or two switching (combination) valves, hoses or
pipes and a relay; some makers add a pressure sensor. P0410 is the general "system malfunction" code; P0411 is
incorrect air flow; P0412 to P0417 are the switching valves; P0418 and P0419 are the pump relays; P0491 and P0492
are insufficient flow; P2430 to P2439 are the pressure sensor; P2440 to P2449 are valves or pump stuck open,
closed, on or off. Owners say "secondary air", "air injection pump", "smog pump", "air switching valve", "SAI".

For each complaint record exactly one CATEGORY and four yes/no FLAGS. You see an excerpt around the matching words
(and the whole narrative when nothing matched). Code what the excerpt supports; if it is cut off at a point that
matters, code what is stated.

## RELEVANCE
N - Not a secondary-air-injection event on THIS vehicle. Use N when:
    - the match is false (an "air pump" for tires or an air suspension or air brakes; "air injection" of a diesel or
      fuel system; "secondary air" meaning an airbag or a bus/truck brake air system; the idle air control valve; an
      air conditioner or an air-assisted tool);
    - the narrative only lists the words among many other complaints, with no statement that this vehicle had a
      secondary-air fault, warning, code, symptom or repair;
    - the words come from another vehicle, a news story or advice, not this vehicle;
    - the system is mentioned only as a part that was checked or replaced during a repair for something clearly
      unrelated, with no link to a secondary-air fault.
    NOT N (relevant) when, on this vehicle: P0410 or a sister code (P0411-P0419, P0491, P0492, P2430-P2449) is named;
    OR the secondary air system, its pump, valve, relay, hose or ports are described as failed, noisy, blocked,
    replaced, blamed, diagnosed or suspected by a shop/dealer/mechanic as the cause of a symptom or warning; OR a
    secondary-air code or symptom is described even if the cause is unknown.

## CATEGORY (one letter) - what was found or done, on this vehicle

P - Air pump. The electric air injection pump (or its motor, or the pump assembly) was named by a shop, dealer or
    mechanic as the cause, or was replaced.
V - Valve. The air switching valve, combination valve, check valve, air control valve or the vacuum/solenoid valve
    that operates it was named as the cause or was replaced.
M - Module or several parts. The whole air injection system/module/assembly was replaced, or the pump and valve (or
    more parts) were replaced together with no single part named as the cause.
W - Electrical. The pump relay, a fuse, wiring, connector, ground, pump power feed, the pressure sensor or the
    control circuit was named as the cause or was repaired/replaced.
L - Lines and passages. A hose, pipe, a clogged or carbon-blocked air port or passage in the cylinder head or exhaust
    manifold, or water/condensation blocking the lines was named as the cause or was cleaned/replaced.
F - Software or campaign only. A reflash/recalibration, recall, TSB, special-coverage or warranty-extension procedure
    was the only repair stated (no part named as cause).
O - Another cause. A repair outside the secondary air system was named as the cause (oxygen sensor, catalytic
    converter, exhaust leak, evaporative system, ECM, engine failure, a different system), or the code or symptom
    was traced to something else.
K - Checked and cleared. The shop or dealer inspected or tested and found no fault, or only cleared the code, with
    no repair; or the light went out by itself and nothing was done.
U - No diagnosis or repair stated. The event is reported but nothing was found or done yet, or the complaint does
    not say; also an owner's own guess, a forum, a code reader or scan with no shop/dealer/mechanic mentioned.

Precedence when more than one fits: use the FINAL repair the complaint reports as having fixed it (or, if it never
got fixed, the cause the shop named last). A part replaced that the owner says did not help does not count. If
several parts were replaced together and no single one is named, use M. A cause the owner merely guesses at does
not count (an owner's "probably the air pump" is U unless a shop or the dealer said it, or the part was replaced by
someone). Among F, O, K, U: F before O before K before U.

## FLAGS (yes/no)

power - the complaint states that because of this fault the vehicle went into limp mode or reduced power, stalled,
    lost power, would not exceed a stated speed, or lit traction/stability warning lights together with the engine light.
fire - the complaint states smoke, a burning or melting smell, heat damage, a melted part, fire or overheating of the
    pump, relay, wiring or hoses because of this fault.
recall - the complaint states that a recall, special coverage, service campaign, extension, TSB or "known issue"
    notice for this vehicle was performed, offered, missing, refused, asked about, or is blamed or credited for this event.
returned - the complaint states that after a repair or a reset the same light, code or symptom came back, or the
    repair did not fix it.

## OUTPUT (one line per complaint, no header)
`odino,category,power,fire,recall,returned,note`
category = one letter from N P V M W L F O K U; flags = yes or no; note = a few words, no commas. For N all flags are no.


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ADDENDUM FOR THE SECOND BATCH (51 complaints found by the completeness check), fingerprinted before that batch was sorted: 2026-10-21T15:16:45Z 80b3a51f7381c32fb11093bdf691b77cf3dfe50e7c66b6274db964e641d017d3  codebook_addendum.md


After the first 508 complaints were sorted, an independent completeness check searched the whole complaint file again for what the first text searches missed. It found 51 more complaints in which the secondary air system is described with words the first searches did not cover:
- the secondary air words with none of the context words required by search 3 (for example "secondary air injection system went out");
- other names for the same system: "secondary injection pump/system/valve", "air intake pump/valve", "air induction pump", "secondary pump", "A.I.R. pump", "2nd air", "SAI", "combi valve", "secondary O2 pump" and similar.
No complaint was found that named a P0410-family code in a spelling the code searches missed.
These 51 are sorted with exactly the same categories, flags, precedence and relevance rule as the first batch, by two independent sorters, and disagreements are decided with the same written rules (R1-R13 of the first batch apply).


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RULES USED TO SETTLE DISAGREEMENTS (R1 to R13; the rule applied to each complaint is in the rule_applied column of the complaints file)
R1 a part counts as the named cause only when a shop, dealer, mechanic or inspection station named it or replaced it. An owner's own reading of codes (code reader, parts-store free scan, own scanner), a forum, or an unnamed "I was told" with nothing replaced is U.
R2 "I had it diagnosed" or "the mechanic's computer showed" followed by a named part counts as a shop naming that part.
R3 a price quote, a warranty or goodwill decision, or "needs replacing" given with a repair estimate implies a dealer diagnosis and counts as the part named.
R4 pump and valve (or more) named or replaced together with no single part singled out -> M. "Second time this year" means an earlier repair happened: use the parts named and returned=yes.
R5 a smog or inspection station finding counts as a shop naming the part.
R6 a recall or campaign that replaces a named part (Subaru 16V738 pump relay) -> W (relay), not F; F is for reflash / procedure with no part named.
R7 recall flag = a recall, campaign, extension or known-issue program for this or a sister model exists and the narrative says it was done, offered, missing, refused or asked about for this vehicle.
R8 power flag: limp mode, reduced power, a speed cap, stalling or nearly stalling because of the fault, or the traction/stability lights lit together with the engine light.
R9 fire flag: smoke, burning smell, melting, fire or overheating of a part. Moisture damage or worn rubber inside a valve is not fire.
R10 only a readiness monitor 'not ready' (no fault, code or symptom) -> N.
R11 a recall about another system (fuel, airbag) that merely appears in the narrative is not the recall flag for this event.
R12 a part replaced that the owner says did not cure the fault does not set the category: use the cause the shop or dealer named last (codebook precedence).
R13 a shop code naming a part of the car's general wiring (not the secondary air circuit) -> O.

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HOW THE SET GREW
First search: 508 complaints (6 name P0410, 182 name a sister code, 465 use secondary air wording). Completeness check: 51 more found, sorted with the same rules. Total 559; 483 relevant, 76 not relevant (N).