Vibration at idle

[deekay911]

My 968 tiptronic vibrates pretty badly when in Drive and at idle. Idle speed is around 950 when in D, and it hunts a little, maybe 10-20 around the 950 mark. If it put it in N, the vibration disappears, so something in the drive train, although not moving, is causing the shudders. Also, even in N, the idle hunts a little.
So, what could cause the transmission vibration? Is there anything I could do to even out the idle?
Thanks guys!
DK

[fast924S]

I would check your motor and tranny mounts

[Lexluther]

Could slack i the tranny do it as well? mine has a kind of vibration, a rough idle feeling, but it doesnt have rough idle.... the car just feels that way sitting in the car. it has NEW engine mounts, I intalled them.

[Tidybuoy]

I just posted this yesterday:

http://forums.pelicanparts.com/showthread.php?t=373662

I also had a vibration problem - just at idle. After replacing my vacuum lines, the vibration went away, in addition to the hunting idle problem that I was having.

I believe the biggest culprit was the small sensor, located just behind the idle control valve. This sensor has two vacuum ports on it and the rubber connectors were very loose.

As I mentioned in my previous post, I replaced all of my vacuum lines over a 6-month period but I really noticed the biggest change when I replaced the hard plastic vacuum tubes - especially the connectors. The rubber connectors, old compared to the new, were very hard and not pliable. I believe this is why my idle and vibration was worse when the engine was cold - especially now that colder weather is setting in.

For the record, my car only has 27k miles on it so I really did not suspect the motor mounts. However, the car is still old and rubber deteriorates. I started with vacuum lines but was going to do the motor mounts next - but the vibration dissapeared after the rubber connectors on the hard plastic vacuum lines.

Hope this helps..............................Vern

[924Sman]

Consider the balance shaft timing?

Dal

[deekay911]

Thanks for all the suggestions. I will be looking at the mounts and the vacuum tubes.
I did the belts just a couple of months ago. The vibration is not present at all when iding in Neutral, only when in Drive, so I am thinking tranny mounts for that, and the vacuum tubes for the uneven idle.