Hi All

I have an Audi A4 2T its a 2006 model I took it to a car shop and they recently replaced the coils and the dump valve, I am now facing an issue whereby when the car is stationary the revs will keep going up and down between two and one RPM's it also happens while I am driving when I switch the manual gear to neutral, I took it to the car shop again and they replaced the clutch pedal switch which did not help at all I am still facing the same issue, they also told me that I have to replace my timing chain does the timing chain have anything to do with the revs counter going up down by itself?? and does the clutch pedal switch have anything to do with revs going up and down by any chance or was I taken for a ride.

 

This was happening to me as well. The car would be stationary and the revs would drop below 1000rpm as normal but then go up to about 1500rpm. This along with a hissing noise after the car was turned off was due to a faulty PCV valve. I then got it replaced with the BSH revamp and the abnormal idle and hissing vanished.

 

mmhhh tnx vozduk I wil ask the mechanic to check the PCV valve so I guess the timing chain and the clutch pedal switch has nothing to do with this

 

A bad clutch pedal switch will usually cause erratic RPM's during shifts, and cruise control usually won't work. An erratic idle would be more along the lines of a failing PCV.

Depending on how many miles you have on the car, maybe the mechanic was just telling you it's time to replace the timing belt, which is typically done around 100-110k.

 

tnx for ur input Damaniac311 I will get my timing chain sorted and the PCV checked out, its jus that I felt cheated becuz I took the car in for the revs that kept on going up and down while the car is stationary instead of fixing that he went and replaced the clutch switch mayb it was "faulty" but my cruise control was working 100% perfect, and before he replaced it I asked him if this will solve the issue and he said yes it will,now that its not solved he is hiding under the timing chain saying if I replace my timing chain then the revs issue will go away he never mentioned anything about the PCV valve

 

My clutch switch went bad and the RPM's only went crazy during shifting not idle, and I lost the cruise. I agree, with the PCV valve suggestion. Also, there was a service action recently involving the PCV valve, and my car's was swiched out under that for free. The car now idle's smoother and the tach needle doesn't "wiggle" anymore. Also, check your oil consumption. If you are going through more oil than usual, that also is a sign the PCV valve is going bad.

 

Can you tell me about what that repair (PCV valve) ought to cost?