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Misfire at 2000rpm (no CEL)

I have a "constant" misfire at around 2000 rpm (cruising) and the engine will stumble a bit as the rpm passes through 2000 rpm on acceleration. The stumble has been occasional since new. The "constant" misfire is new. This is with the Track Key. No CEL.

I did read through the sticky above. Common themes appear to be crank sensor and plug and TSB 13-6-15. Thoughts?

r/
Eric
 
Update...ran the the silver key for 5 min at idle (cam zero position relearn) and then restarted with the red key. The misfire is gone. Never did get a CEL. Seems ok now.
 
You can reset your PCM by either disconnecting your battery for 10+ minutes or crossing the red and black cables. I prefer disconnecting the ground wire myself. I've done this a couple of times now when my car starting running a big rough and that fixed it.
 
Eric said:
Update...ran the the silver key for 5 min at idle (cam zero position relearn) and then restarted with the red key. The misfire is gone. Never did get a CEL. Seems ok now.

Glad the misfire is gone, but is the constant stumble still there? I have the exact same issue with my car since it was new. I've done the battery disconnect for 10 mins and really didn't notice much.
 
Disconnecting the battery didn't change much for me either. Doing the cam zero position re-learn (5 min idle with silver key) was a noticeable difference. The stumble wasn't there afterwards and the misfire was gone.

I do wonder if we are getting quality gas these days as they switch from winter to summer blends from different refineries. I originally attributed the stumble to gas since it was intermittent. When the low rpm misfire appeared, that was something different....and it was only with the red key.
 
Eric said:
Disconnecting the battery didn't change much for me either. Doing the cam zero position re-learn (5 min idle with silver key) was a noticeable difference. The stumble wasn't there afterwards and the misfire was gone.


Would it make sense to do the cam zero position re-learn on a vehicle that hasnt had trackey intalled? I' ve yet to install trackey. This may be a stupid question, but how do you do the cam zero position re-learn? Is it literally just starting up your car with the silver key and letting it idle for 5 minutes?
 
Not sure since you don't have the TK installed. The TK instructions discuss the cam zero position relearn.

Have you tried disconnecting the battery for 10+ minutes and then idle it for 5 min (no accessories on, don't touch the throttle)? Might be a trip to the dealer....I see you have a 2012, believe TSB 13-6-15 applies.

r/
Eric
 

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