The Lemon IndexP129F is a manufacturer-specific code, so its exact meaning depends on the make. Full P129F page
10 owner complaints · the #2 code GMC Terrain owners name · 13% of GMC Terrain complaints that name a code (every car: 0.4%)
2020–2022 GMC Terrain · most: 2022 (9), 2020 (1)
GMC Terrain owners named P129F in 10 complaints to the U.S. government (NHTSA), most often on the 2022 and 2020 model years. The part they name most is the fuel pump (6 complaints). Complaints are owner reports, not proof of a defect.
GMC Terrain model years that report P129F
Owner complaints naming P129F, by model year. Raw counts: years that sold more get more complaints, so this is each model year's record, not a failure rate.
What owners say caused it or fixed it
The most-named part is the fuel pump, in 6 of the 10 complaints (60%). 1 of those mention it being replaced or repaired.
- Fuel pump6 complaints1 mentions a repair or replacement · what owners paid
7 complaints mention a recall.
Counted from the owners' own words: a part counts when a sentence names it with a cause or repair word. What owners wrote, not a diagnosis. A shop should confirm the cause before replacing parts.
Symptoms owners describe with P129F
40% of these complaints say the check engine light came on.
- Stalls or shuts off70%7 of 10 complaints
- Loses power or goes into limp mode20%2 of 10 complaints
Share of the complaints naming P129F whose text also describes each problem. A complaint can describe more than one.
Keep going
- P129F: meaning, causes and every car that reports it
- GMC Terrain reliability by year
- 2022 GMC Terrain problems and recalls
Other codes GMC Terrain owners report
P129F on other cars
Chevrolet Equinox (12) · GMC Sierra (12) · Chevrolet Silverado (11)
The details
How we count
We read every owner complaint in the NHTSA file whose text names this trouble code, and count the ones filed about this model (matched by the make, model and model year on the complaint). Mileage is what the owner entered on the form.
Parts: a complaint counts for a part when one of the owner's own sentences names that part together with a cause word (failed, bad, diagnosed, caused by, leaking ...) or a repair word (replaced, repaired, new, reprogrammed ...). "Came back" means the same complaint also says the problem returned or the repair didn't fix it. These are counts of what owners wrote, not a diagnosis, and one complaint can name several parts.
Complaints are reports, not proof of a defect, and most owners never file one. Popular models get more complaints, so the counts are not a failure rate. The code meaning is the standard SAE J2012 definition in our own words, or the carmaker's meaning where we verified it for that make.
What P129F means
P129F is a manufacturer-specific code: each carmaker decides what it means, so the same code can point to different problems on different brands. We haven't verified its meaning for Gmc yet. A dealer or a scanner with the maker's software can tell you exactly.
Check the complaints yourself
NHTSA complaint numbers (search them at nhtsa.gov): 11763875, 11759454, 11759425, 11759287, 11757080, 11746008, 11726130, 11655646, 11645920, 11598066.
Quick answers
Which GMC Terrain years have the most P129F complaints?
In complaints to NHTSA, owners of the 2022 (9), 2020 (1) GMC Terrain named P129F most (10 complaints in all, 2020–2022). Raw counts, not a failure rate.
What fixes P129F on a GMC Terrain?
Owners most often name the fuel pump (6 of 10 complaints). That's what owners wrote, not a diagnosis: have a shop confirm the cause with a scan and tests before replacing parts.
Sources: NHTSA owner complaints that name P129F on the GMC Terrain, counted by The Lemon Index; NHTSA recalls; repair bills owners named. Meanings: SAE J2012 in our own words. Owner reports, not a diagnosis or repair advice for your car.