What would cause misfire only when A/C comp. is on?

Question

P0300 set when ac is turned on. I can see on the scanner that #4 is misfiring. Shut the comp off and it immediately stops misfire. I have swapped coils and changed MAF but still the same. Also performed injector clean with AC cleaner. 2012 Buick Regal 2.0 turbo.

Answer 1

Hi there,

Here is a list of possible causes for a misfire code.

P0300 BUICK - Cylinder Misfire Detected Random Cylinders

Read more: https://www.autocodes.com/p0300_buick.html