I own a 84 944 for 2 years now. The car has only 60,000 miles on it. It drives excellent. What I am experiencing is despite the power and excellent handling there is a slight vibration everytime the car is between 3500 - 4000 rpm. Regardles of speed. Over 4000 rpmit drives smoothly. I tried several times to hit speed of 90mph and the vibration came up. At close to 100mph the vibration disappears. I only tried to keep it a little over a hundred but backed off early enough as dont see any reason to keep it at that speed. This is the only problem I am having with this car. I have read a lot of problems on 944 and I never heard anything like this. If anyone could give me any idea as to what it is or if it is normal I would really appreciate it. Other than that I love the car and I trust the car will get me from poing to point without problem.

Thanks to all you 944ners.

 

Where is the vibration at? The steering wheel? The engine bay?

 

The vibration comes from the engine bay. Thanks for yourhelp.

 

Then either you have a balance shaft out of time, or bad engine mounts. Typically engine mounts make vibration at idle and go away up top, where as a balance shaft out of time is fine at idle, but crazy around 4k rpms.

 

Thanks for the info. Ill try to have my balance shaft timing checked.

 

I think Doc Wilen is right on, I had an '89 n/a with same symptoms and the balance shaft belt had skipped a tooth or two, as it was improperly retensioned 1500 miles or so after a new one was installed. If you don't know the age of the belt, you might want to have this looked at sooner than later.
PeterA