pete000

Just got a check engine light yesterday. Did a check and came up with P0301 "Cylinder 1 missfire". Car runs fine, not sure what happened.

Any ideas why?

Loren

Are you sure that is the only fault code?

pete000

I used a Actron scanner and it listed only one fault.

I am going to be investing in a Durametric set up shortly and recheck it. Might be more thorogh.

I have reset the check engine light and have to drive it a while to se if it retrips.

Macster

engine symptoms is probably nothing to lose much sleep over.

I do not know the car's history, but it may have been used in such a way, fed a sub-par brand of gasoline, that has allowed engine deposits to gather.

These can affect air flow/fuel flow into the cylinder (especially when these deposits, as they are wont to do, accumulate on the intake side of the intake valves) to the point improper combustion, aka misfire, occurs.

It might be worth the effort to subject the car to a dose or two of Techron, following the directions on the bottle. And I always like to follow a short time after the last tank of gas treated with a bottle of Techron has been consumed with an engine oil/filter service to drain and replace the old oil almost certainly contaminated with at least some of the crud loosened by teh Techron.

If the misfire returns, becomes frequent, or if the engine's behavior changes during cold/warm/hot starts, idling, part or full throttle operation, then you need to seek professional help in promptly diagnosing what is going on.

While I don't think this is the case for your engine, a co-workers '02 Subie developed a frequent misfire that ultimately was traced to a burned exhaust valve.

Sincerely,

Macster.