wrightbenz

I am going to go look at a 1986 944na that has a knocking sound. The guys mechanic said it sounds like valve train noise. ANy ideas what it may be. They said the car seems to run fine but they shut it down right away to prevent damage.

thanks

Mighty Shilling

it might be a collapsed lifter or it might be a spun bearing.

joemis

I had the following experience the other morning with my 89 s2: Started the car after sitting for about a week - loud knocking sound. let it idle for about a minute, while I looked under the hood. Sound appeared to be coming from the top of the engine. Shut it down and searched for similar stories on rennlist.

Saw the following remedy that someone had posted: Pulled the DME relay. Cranked the engine with the starter for about 20 seconds to get some oil circulation going. repeated the cranking 2 more times. Replaced the DME relay. Fired the engine.

Sound was now more like a typical worn valve lifter. Let the engine idle for about 10 minutes, sound mostly went away. Drove the car for about 3 miles (kept the rpm's down) and sound was completely gone.

Took the car to work the next day (100 miles round trip), no engine noises, no issues.

I don't know if this method will work for you , but it did work for me.

Joe M.

1989 944 s2

Calmchaos

Is it more of a ticking or a real knocking sound?...
When I got my rod knock it was enough to make the engine shake a little bit.

jtsporsche

i have a Knocking/Tapping noise also from the top/front of the engine. but it only does it when the motor is still cold. after about ten minutes of driving, it goes away.
i also searched rennlist for answers, i learned it could be a "stuck" lifter, or whatever. so i poured some seafoam in it...didnt work

joemis- what is that method supposed to accomplish? obviousley stopping the sound, but how?

joemis

It is supposed to allow a collapsed lifter to get pumped up with oil. I don't know why turning over with the starter would be any different that letting the engine idle.

You might try putting a pint of Marvel Mystery Oil in your crankcase. It's a light red oil that helps to break up sludge, deposits etc. that might be preventing good oil flow to your lifters. I would put it in 100 miles or so before your next oil change that way deposits it breaks up will get flushed out.

Give it a try and let us know if it helps..

jtsporsche

i still have mabey a month and a half to go before my oil needs changing. if it helps, i may start a new thread to tell everyone.

trackdaycareracer

Thanks for posting this, helped me out today Went from expensive engine rebuild to absolutely no problem in less than five minutes after reading your post.