I took my car into the shop when the “Check Engine” light came on. I noticed the engine was running a little rough, and the mechanic told me the code said one of the cylinders wasn’t firing. He checked the spark plug, the spark plug wire, and the coil, and told me that all three were working, that I’d have to bring the car back in the morning for a compression test in order to figure out what the problem is, and that it probably won’t be worth the cost to repair it.
I was planning to bring it in Monday morning for the compression test, but when I was driving home this evening, the “Check Engine” light suddenly went off, and I noticed the engine was no longer running rough.
I don’t understand what kind of problem would clear itself up as suddenly as it originally occurred. When I bring it back for testing, what else should I ask the mechanic to check for?
The car is a 2005 Buick LaCrosse, and it has 152,000 miles on the odometer.