QuestionI bought this car 6 month ago, no maintenance history available. Shortly after the regular oil and filter change at approx. 140k, some high pitching noise was noticable, coming from the engine compartment. I found some over pressure in the crankshaft ventilation system (oil spilling after removing oil filler cap) and I checked the flame trap and found it clogged on the small vacuum hose side, going to the intake manifold. The clogging was very hard and it seemed to me like it was there for a long time already. I removed all the clogging by use of a small drill bit and re-installed it, enigne was running fine, no over pressure anymore and noise was gone. After 1-2 weeks, noise came back. This time I replaced the flame trap completely by a new one but noise remains, no high pressure in the PCV and no clogged hoses.
Noise is most noticable when car is cold (common piston slap noise disappears after warming up) and always under acceleration. Besides that, car is running fine, no power loss, no excessive oil consumption, no smoke, no water in oil or oil in cooling water, no other symptoms.
I was wondering if just the valves need re-adjustment or something different, more serious could be the problem. I did not yet perform a compression test.
Any suggestion where to look next?
Thanks a lot for your advice.
Regards,
Markus
Answermake sure you clean the nipple for flame trap in the intake manifold, and make sure underneath flame trap is not clogged (kind of part of oil pan) and all hoses too, i would change all of them, as for the noises , its usually just the fan belts slipping, change them first, could be water pump or pulley for timing belt? i wouldn't tear that apart first though
