OBD-II Generic Error Code P2429: How to Fix It

Q: Can I keep driving with a P2429 code?

Short local trips may be possible, but you should avoid highway driving, heavy towing, or high-load situations. Sustained high exhaust temperatures can destroy your catalytic converter, damage turbocharger seals, or cause head gasket failure. Get the vehicle diagnosed as soon as possible.

Q: What is the most common cause of P2429?

The most common causes are a faulty EGT sensor giving a false high reading, a lean fuel condition caused by a vacuum leak or weak fuel injector, a stuck-closed EGR valve, or ignition misfires sending unburned fuel into the exhaust. Always check the sensor itself before replacing expensive components.

Q: Is P2429 the same as P2428?

No. P2428 refers to exhaust gas temperature too high on Bank 1 (the side containing cylinder #1), while P2429 specifically refers to Bank 2 (the opposite side). The diagnostic steps are similar, but you must focus your inspection on the Bank 2 side of the engine and exhaust system.

Q: How much does it cost to fix a P2429 code?

Cost varies widely by root cause. An EGT sensor replacement typically costs $80–$250 in parts and labor. An EGR valve cleaning or replacement runs $150–$400. Catalytic converter replacement can cost $500–$2,000+. Diagnosing and fixing a lean fuel condition (vacuum leaks, injectors) generally runs $100–$600 depending on what is found.

Q: Will P2429 cause a failed emissions test?

Yes, in most cases. P2429 will illuminate your check engine light, which automatically causes a failure in OBD-based emissions testing in most U.S. states. The underlying issue — high EGT, a damaged catalytic converter, or a lean mixture — may also cause elevated tailpipe emissions that fail a sniffer test. Repair the fault and complete a drive cycle to set all readiness monitors before retesting.

Abstract

The P2429 code means your vehicle's onboard diagnostic system has detected that the exhaust gas temperature (EGT) on Bank 2 is exceeding safe operating limits. Bank 2 refers to the side of the engine that does NOT contain cylinder #1. This is a medium-severity code that can lead to serious engine and emissions system damage — including a damaged catalytic converter or turbocharger — if left unaddressed.