cayenne idle drop engine vibrates when coming to stop

[rpcc]

I've had the same issue - in my 2004 CS.  Turns out some dude taped a broken vent hose from the separator to the intake - $150 later and a new vent hose the vibration its nearly gone, but not 100%.   I'm guessing this could be another hose or engine mounts or maybe the dogbone mount.  It would be great to know how to smoke test the system - anyone have a diy on this?

[rpcc]

I think this is the next set of steps to try - http://www.pelicanparts.com/techarticles/Porsche-Cayenne/69-FUEL-Fixing_Common_Vacuum_Leaks/69-FUEL-Fixing_Common_Vacuum_Leaks.htm

[ALEV8]

Tried to buy a 997 today and couldnt do it......still love the 955 too much. That is saying something.

[mihaipopa]

Anyone know of a easy (cheap) way to test smoke the vacuum system?

[Loren]

Anyone know of a easy (cheap) way to test smoke the vacuum system?

 

You need to find a shop with a smoke machine. Most good shops have them.

[mihaipopa]

Thanks, Loren.

Any idea what a reasonable price would be for that sort of job?

Just wondering if anyone had success with diy party fog machines, cigars, etc.?

Thanks!

[Loren]

These smoke machines are not a DIY project - a real cost about $1000 retail.

I would think a good shop should charge you an hour or so labor -- and they should find the leak.

[ericstaup]

The vibration has gotten better after about 5000 miles since my last post about this. Replaced the fule filters about 5000 ago but that didn't help any at the time. I would say the problem is about 50% better. Maybe waiting and seeing pays off occasionally. Really has gone from very irritating to not so noticeable.

Eric

[ALEV8]

Nope it's the mounts, trust us.....

[srfrdrew]

Is there a diy for the engine mounts out there?

I read the non turbos are "relatively" easy to change and can get around lifting engine with non turbo

[ALEV8]

Don't poor boy an engine mount install...................

[srfrdrew]

What are the costs out there to replace the Engine Mounts at dealer and/or independent?

[jpru2001]

I know most on here have a more significant issue, but I developed the idle drop vibration...relearned throttle response (thanks Loren) solved it 50%...ran a tank of Techron...relearned it again...90% gone.  About to do plugs and clean throttle body and see if that knocks it out...if not, I am sure the remaining slight vibration is engine mounts...but for a grand I am going to live with it.  :-)

[ALEV8]

Not quite solved homie.....you'll get to engine mounts soon enough.

[ALEV8]

just keep going.

Edited March 6, 2015 by ALEV8

[jpru2001]

We had good weather today and I drive home with no AC....no vibration at all...I saw several people trying that but never saw the explanation of what a likely diagnosis is if that is the case....any guidance?

[mihaipopa]

what i've noticed so far: the vibration is diminished when:

 

- warm weather (winter vs summer, morning vs afternoon)

- warm engine vs cold engine (regardless of climate)

-no AC/Heat on

 

also, no vibration when in Neutral, or when slowly crawling to a stop

[ALEV8]

Engine mounts.

Stop wasting time.

Engine mounts.

[mihaipopa]

:) brilliant, alev8.

sounds like an sos for engine mounts.

and i do think you're right.. nothing has worked so far

[ferrytrip1]

echo most of the replies - had bad vibe on idle when I got my car - two indies both said engine mounts.  Had them replaced - smooth as a smooth thing on a smooth day now

[bigbuzuki]

Change the engine mounts and the transmission mount whilst your there.

[ALEV8]

Bingo. I would do it if it weren't so FING expensive

[wvicary]

Mounts will reduce the vibration transmitted but not stop the actual idle control fault which is causing the shudder in the first place.

[ALEV8]

The P tech who drove my car had no issue and my idle does not move at all when read by Durametric despite the shudder, and mine is still doing it. What fault are you referring to?

Edited March 12, 2015 by ALEV8

[srfrdrew]

Keep the talk going, we'll all get this common issue solved once an for all.  This common issue should be condensed into a "sticky" as this sounds like a very common issue.

 

I have also read that besides a "vacuum" issue that causes the quick idle drop, it is more likely the timing chain that "stretches" over time causing the quick and noticeable drop in idle when coming to a stop.

Edited March 13, 2015 by srfrdrew