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Q: I have oil smoking out of my oil dip stick and oil filler on my valve cover. Lots of smoke coming out of my PCV valve

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I have a lot of smoke coming out of my oil dipstick, my oil cap, and when I remove the pcv valve while the car is running, a lot of smoke comes out. The pcv valve still has lots of suction and I just replaced the valve cover gasket so I don't think it would be those. The car still runs fine but it's a bit more shakey when stoped at a red light or anytime the car is stopped while in park or reverse. Any other advice on what it could be?

My car has 50000 miles.
My car has an automatic transmission.

A: Hey there. Worn piston rings create more cr...

Hey there. Worn piston rings create more crankcase fumes (i.e. the smoke you see coming out of breather tubes and orifices). This is called "blow-by". As long as the PCV valve stays clear, and the engine can handle the fume/clean air & fuel mix, then you should be fine.

This is a normal stage of wear as long as tailpipe blue smoke doesn’t become excessive or offensive. The rough running at a stop light may be an early indication of too much blow-by, although those 6 cylinders engines had trouble with rough idle/low speed because of the big differences in the distance between the carb and each cylinder (Cyl 1 & 6 distant, cyl 3 & 4 very close). Keep it tuned, and watch for slow degradation in low-speed running. If you notice this problem worsen or would like to have this checked, then have a qualified professional from YourMechanic come to your car’s location to inspect the smoking problem and follow through with repairs.

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