Porsche Repair: 1987 944 Engine Vibrate on idle, camshaft lobes, airflow meter

Question
I have a 1987 944 N, the engine shakes or vibrate on idle but it runs perfectly fine. I noticed no hesitations nor sputter on the engine when it's doing 15 miles/hour or so. What could couse this problem? I also noticed engine oil coming up to the Airflow meter. Please, advise.

Greg

Answer
Hi Greg,

Your being so observant as to notice oil up at the airflow meter has me a bit perplexed.

If you consider the most likely possibilities to cause your problem, the list would look like this:
1. vacuum leak, 2. air filter clogged. 3. weak fuel pump, 4. leaking head gasket, 5. camshaft lobes worn....

If there's a connection betweeb the oil you see at the airflow meter and the idle problem, my intuition says you've got a leaky head gasket.  Up to this point I can't find a reasonable explanation though.  

So my suggestion would be to look into all the areas I've mentioned for possible answers.  For the leaky head gasket, do  a compression test.  If you find one cylinder with abnormally low compression, you've found the leak in the head gasket.

If you'd like to ask a follow-up question as you proceed please feel free.

Dave