Intermittent fast idle

[Scottyjohn]

Hi all,
Am going to pop my car onto VAG-com this week, but any ideas as to possible causes would be appreciated?
The car runbs fine, but occasionally with no set pattern, the cars idle creeps up to about 1050 - 1100 rpm and sits there. It happens when its hot or cold, and seems to be totally random. Sometimes a rev will clear it, other times it just clears itself and goes back to normal idle.

Any pointers would be greatly appreciated!

Its a 2001 1.9 TDI 130 Cheers!

[ram33]

Hi all,
Am going to pop my car onto VAG-com this week, but any ideas as to possible causes would be appreciated?
The car runbs fine, but occasionally with no set pattern, the cars idle creeps up to about 1050 - 1100 rpm and sits there. It happens when its hot or cold, and seems to be totally random. Sometimes a rev will clear it, other times it just clears itself and goes back to normal idle.

Any pointers would be greatly appreciated!

Its a 2001 1.9 TDI 130 Cheers!

ive got the same problem on my 19 tdi 130 (2003)
it shows error msg on vagcom - cant remember what it said off hand, but it will almost certainly be the temp sensor near the bulkhead. well known problem
no bothered changing mine yet as its not much of a problem to me

[RickT]

I had this on mine a while back..

it was due to a leak in a vacum hose casuing it to over rev..

Lift the bonnet and blip the thottle listening for any air hissing... best to get some one to blip it while you get your head under the bonnet...

check the hoses around the back of the engine block first as these are the first to go..

Rick

[taff3526]

hi............have been told that this could be the ECU increasing the revs as the alternator may be faulty........anyone shred any light on this?

[blackpool1974]

hi............have been told that this could be the ECU increasing the revs as the alternator may be faulty........anyone shred any light on this?

many reasons for over revving (is it rough at idle) could be due to vacuum leaks or crankcase breather valves that are knackered or even a dirty throttle valve

Have you got the vagcom codes logged for

engine running lean ??
idle higher than expected ??

[nevo]

Had the very same problem on my wifes golf tdi would occassionly start" hunting" going to 1000-1150 revs ,sometimes when driving it would speed up when you did'nt want it !, changed the maf in the end, sorted it.