{2010 GMC Acadia SLT O2 Sensors}
2 Answers
I'm getting a fuel trim system too rich error (p2099) at bank 2 I just replaced my ignition coils and spark plugs and now I'm getting a missfiring at cylinder 3
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It’s really easy to crack a spark plug on one of these pull the misfired plug and check it over closely the crack will be small. As far as rich on one bank it can be an upstream O2 sensor on that bank but I would do a live data scan and bring up the O2 sensors on the screen and see if any of them are dead or not cycling. I have seen leaking injectors also cause rich conditions, fuel contaminated engine oil, vapor canister valve stuck open.