brooklynkid

hey guys,
I noticed that my cayenne shudders when slowing down to around 5 mph the RPMs dip below 500 rpms for a second. Ive had a few mechanics and a transmission specialist look at the cayenne and neither thinks the tranny or the motor mounts. What are your thoughts? throttle postion sensor, fuel pump?
thx
brooklynkid

Dilberto

Coils?

brooklynkid

i ran scanner , no codes and previous owner had coils and plugs recently changed.

the cars got 140k on it, I figure the throttle body must be filthy, gonna give it a good cleaning this weekend

fortysixandtwo

Mine does almost the same thing. The rpm will dip from about 590 to 500 rpm for a second while slowing down through the 4mph range.

Based on this post I'm hoping this will go away when replacing the original fuel pumps. https://rennlist.com/forums/porsche-...em-solved.html

brooklynkid

if cleaning maf and throttle body and relearning the throttle doesnt work im gonna check fuel pressure

bigbuzuki

Some info on a common issue.
http://www.renntech.org/forums/topic...gain/?p=260617

mudman2

I would look at 2 things first, fuel pumps will fail or are failing now at that mileage/age

Battery, can cause all sorts of silly things

the others are still candidates but pumps would be my first bet

brooklynkid

looks like the previous owner did some work on fuel pumps, but I reset throttle and its better by 50%. Also changed out torque dampener which was almost completely rotted out!

fortysixandtwo

Looks like we're both tracking down the same issues with our new to us CTTs.
The engine will feel noticeably smoother with the new torque reaction arm. Put mine in last week.

brooklynkid

I load tested battery and it failed!

MUDMAN, you rock! sears had $15 off car batteries and they had a good tech that worked on germans. After replacing battery and resetting computer and changing a blown fuse, i reset throttle position and it idles at 700-800rpms

NO SHUDDER WHEN DECELERATING!

CANT BELIEVE IT WAS JUST BATTERY

mudman2

strange things do happen with old batteries

glad its sorted

Travis

Brooklynkid,

Which fuse was blown?

5678

A few questions:

- How do you reset the throttle pedal?
- What's the torque reaction arm?

brooklynkid

cant which number fuse, but we found it cause the durametric wasnt getting power. tech said it also powered one of the cigarette lighters too.

brooklynkid

reset throttle by turning key to on position for 1 min, listen for little gremlins
moving around. turn to off postion and restart car. drive 5 miles

torque dampener is brace on R bank of engine