Q: What makes the check engine light come on?

asked by on November 04, 2015

The other day when I was driving my 2012 Jeep Wrangler I noticed that the check engine light had turned on. This was worrying to me, as this vehicle is pretty new at only 16,000 miles. I parked it for a minute and when I started it back up the light had gone away. A day later the light was back and there was a ticking noise coming from the engine. I am worried that there is a problem with the head. Is there any reason for this in a new vehicle other than a defective part?

The drive complaint you described seems to be an engine misfire, which can be verified by scanning the cars computer for an error code. If you get a code P0300, P0302, P0304 or P0306 then Jeep has issued a Technical Service Bulletin (TSB) 09-002-14 dated 12/15/2014. The TSB entails checking for the above codes and testing cylinder leakage. If it turns out to be a defective cylinder head, it will need to be replaced. Jeep has extended the warranty status on this complaint so the dealership should cover the repairs.

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