During car wash some water might have seeped into the alternator and the car was misfiring slightly at low speed. I drove about 150km. While cleaning the alternator and spark plugs i noticed some oil on one plug, Could it be because of misfiring or something else ? Also the car is running smoothly now.
Oil on spark plug ? is it like a engine oil or it just carbon and some petrol on it? What car is that ? Oil in the combustion cylinder can enter when the rings around the piston cylinder are worn out , in that case the piston rings act as suction pump. that can suck oil .. but to notice that accelrate the car and you will smoke coming out of the exhaust. Double check those things. Wait for Dhhawal too , he might have some other symptoms
my friend had the same problem with his integra, his got messed because the car sat for 6 months, but after driving it around for a while it jus get better.
get a compression test done at a local garage, wet and a dry comp test, that should tell you conclusively if the rings are in fact worn out, more than 20 percent variation means your rings are worn out, do it on all the cylinders to get some sort of reference, other than what codename has mentioned also check your oil consumption, that is a decent indicator of worn piston rings
Change the spark plug tube gasket and the valve cover gasket while you are doing it take out the plugs to let the oil drip into the pistons, the spark plugs failed to function normally and the oil stick onto them.
i am sorry could you please elaborate, what do you mean by taking out the spark plugs and let the oil drip into the pistons? what do you mean when you say the spark plugs failed to function normally?
Yes, I have also the same thing notices in my car. This oil due to you are car is cool and not warm enough. That's why engine oil get in spark. Don't worry about it, this problem will be solved automatically.