poor-sh-nut

When my 87 944 is at idle I have a very bad shudder/vibration. When I give it gas and the rpms go to around 1100 the car is as smooth as silk. I have only had the car a few weeks so I don't know much of the history about it. My first take is that possibly the balance shafts are slightly out of adjustment. But I also notice that the idle RPM's fluctuate between approximately 800 to 900 rpm (constantly when at idle) This could possibly be a bad Idle Stabilizer. What do you think?

Thanks Terry

voodooecon

sounds like motor mounts. my understanding of balance shafts is that if they we're out of adjustment the vibration would get worse has you rev, not better (at a quadratic rate, so it would be noticeable).

I had such a bad vibration that i couldnt believe it was just the motor mounts - i replaced them both (you should do both if you're going to do either) and it make an unbelieveable difference.