GMC Troubleshooting Questions? Ask a Mechanic for Answers
Is the check engine light on when this is happening?
What trouble codes are you logging as this is going on?
I'm sorry for the delay, I was supposed to get an email notification that you had responded, but I didn't get that notification.
P1345 means you need to perform the crankshaft variation learn procedure, but this won't cause an idle issue, or any other issue, for that matter.
What is the fuel trim doing when it's idling high like this?
What did you find, out of curiosity?
Did you get this worked out? Wanted to follow up and make sure you got what you needed from me.
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