Idle Increase ?

[Rosie]

Hi All

 

I have a 1999 110 tdi Gal.She (rosie) normally idles at about 800rpm,but today she has changed ( I know its a womans perogative ).She starts at 800rpm for about 10 secs then increases to 1100rpm for no apparent reason.This stays the same until ignition switched off then same process again.

 

Any ideas why ?

 

Many thanks :rolleyes:

[chrispb123456]

Scan with Vagcom first if possible, but if not try a new temperature sensor.

[Rosie]

Hi

 

Sorted the problem.Defective Alternator.The Alt was producing the incorrect charge which resulted in ECU not recieving the right readings from the sensors,which led the ECU to believe the engine was always running cold ,hence put more fuel into the system,hence higher revs.

New Alt fitted and car now back to normal