P029E
Cylinder 2 - Fuel Trim at Max Limit
Fuel & air metering
Generic OBD-II
High
What it means
P029E means the ECM has pushed cylinder 2's fuel trim to its maximum limit — it's adding as much fuel as it can to that cylinder and still can't reach the target mixture, so cylinder 2 is running lean. The usual causes are a restricted injector, a localized air or vacuum leak, or low fuel pressure.
High
Can I keep driving? Driveable short-term, but a persistently lean cylinder 2 can misfire and stress the converter — address it soon.
Common symptoms
What you'll notice
- Check-engine light on
- Rough idle or slight misfire
- Possible hard starting when cold
- Hesitation or reduced power
Common causes
Most likely first
- Restricted or dirty cylinder 2 injectorLikely
- Intake or vacuum leak affecting cylinder 2Common
- Low fuel pressure or weak fuel deliveryCommon
- Skewed MAF or oxygen-sensor readingLess often
- Exhaust leak near the O2 sensor pulling in airLess often
How to diagnose & fix
Work through it in order
- Read freeze-frame and review overall and cylinder-specific fuel-trim data.
- Inspect for intake/vacuum leaks around cylinder 2, including the PCV connection.
- Check fuel pressure and injector flow; clean or replace a restricted cylinder 2 injector.
- Verify MAF and O2 sensor readings and check for exhaust leaks.
- Repair the lean cause, then clear and re-test.
FAQ
Quick answers
Is it safe to drive with P029E?+
Short-term yes, but a persistently lean cylinder can misfire and, over time, harm the catalytic converter or pistons. Address it soon.
Can I just clear P029E?+
It returns once the ECM again maxes out fuel trim on cylinder 2; the lean condition must be fixed.
Related codes
Often seen with P029E
Read & clear P029E yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX