I have an infrequent misfire like a bad plug etc when idling. It may misfire at speed but I don't feel it. Have had it to the dealer twice and an authorized Volvo Service Shop once-no codes and, of course, it doesn't skip for them. This has been occurring on and off for the past 6 months.

I am wondering about things like the coil or perhaps if moisture is getting to something. It was raining yesterday and today when it misfired again.

Anyone have any suggestions. Oh. It's been completely tuned up by the dealer about 1 month ago. 99 S70 GLT with about 55,000 on the engine.

Love these "intermittent" problems!

Thanks

Your engine doesn't have a coil, it has 5 of them, sitting over the spark plugs. Each one is not cheap, but they can and will die from the engine heat. Usually #3 or #4. But, you have no codes. So that means you do not have an ignition problem.

You could have a fuel delivery problem, they never throw codes when they fail.

When has your fuel filter been changed? They only cost $15-18 and take little time to replace. They should be replaced about 80K miles or so, depending on the brand of gasoline you buy.

You could also have a sticky fuel injector, a little cleaner goes a long way.

Klaus
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The 164 has a new home, all I am left with are a 95 854T and a 98 V70R :)