lot's of vibration when running stationary

[porsche356]

Hi,

Just picked up my c2s (2005, 997) from the dealer after (a very expensive) big 25.0000 miles service.

Everything is ok, except for one thing. When I stop the car (leave the engine running), the car suddenly vibrates quite heavily (when in gear, tiptronic). When I use the throttle is goes away. This was not there in the past. I took a look at the bill and saw that they cleaned the gas throttle house and 'reprogrammed' it. Could this be the cause?

I went by the dealer yesterday and they said that the vibrations are completely normal. Fine, but they were not there before and besides that, I find them rather annoying. Any ideas?

Regards, frank

Edited October 1, 2009 by porsche356

[cvhs18472]

At what RPM is the engine ideling? Maybe they "adjusted the idle" and it is now too low. Just an idea. Ed

[porsche356]

Looked at this as well: 820-840 rpm's.

That's normal right?

[phillipj]

Hi,

Just picked up my c2s (2005, 997) from the dealer after (a very expensive) big 25.0000 miles service.

Everything is ok, except for one thing. When I stop the car (leave the engine running), the car suddenly vibrates quite heavily (when in gear, tiptronic). When I use the throttle is goes away. This was not there in the past. I took a look at the bill and saw that they cleaned the gas throttle house and 'reprogrammed' it. Could this be the cause?

I went by the dealer yesterday and they said that the vibrations are completely normal. Fine, but they were not there before and besides that, I find them rather annoying. Any ideas?

Regards, frank

Frank,

Why was a major service required at 25k miles? The 20K service is minor. You dont have a major service until 40k miles. Is this what your dealer told you? You can down losd the service schedule from this site so you can see the intervals for yourself.

Regarding the vibration I would have them make it right. I hate dealers..

[porsche356]

The service was the one meant after 4 year (plugs, big service etc).

Was wrong about the RPM's: more 650!

Noticed some shahing under desceleration as well. Car shakes very light. No strange sounds.

The mystery continues.

Regards, frank

[Dharn55]

Did you check the motor mounts?

[porsche356]

I did not check the motormounts. The car was fine and all of a sudden, after the service, including MAF cleaning, the problem occured.

Obviously I went back to the dealer. They told me that the vibrations were normal. But again, this was not there in the past. Therefore I suspected the MAF sensor. Anyway to on the motormounts?

Regards, frank

[dphatch]

I did not check the motormounts. The car was fine and all of a sudden, after the service, including MAF cleaning, the problem occured.

Obviously I went back to the dealer. They told me that the vibrations were normal. But again, this was not there in the past. Therefore I suspected the MAF sensor. Anyway to on the motormounts?

Regards, frank

BS on the "it's normal" response. If it wasn't doing it before they screwed with stuff that didn't need screwing with than it needs to be put right. If the dealer won't do it get hold of Porsche's regional office and tell them your story and tell them you want it to run they way it did before you brought to the dealer for service. Once it's fixed to your satisfaction find another dealer to do business with, preferably one that doesn't use the 'it's normal" excuse when they screw up and don't want to admit it. Shaking could be caused by a misfire. PIWIS read should indicate anything that's amiss with the engine. They should check for codes. Could be a disconnected vacuum line on the intake. I'm not sure why they would mess with motor mounts during any regular service.