Unstable Idling?

Post by **alexperkins** » Wed Jul 02, 2008 11:44 pm

Hi All

GTI is being a bit odd - if for example you start the engine, then turn on the AC or the HIDS, the idling starts to pulse - it does it so drawingly, the sidelights or interior light will dim as it pulses.

When you drive it, there are no problems at all...just when it returns to idle

Any ideas? Before anyone says, the throttle body is cleaned

Cheers

Alex

Tim_GTi · Post by **Tim_GTi** » Thu Jul 03, 2008 12:11 am

Just wait for the next fuel fill mate

92 rocks · Post by **92 rocks** » Thu Jul 03, 2008 7:54 pm

fuel tank vent clear?

aux belt adjusted ok?

tegwin · Post by **tegwin** » Thu Jul 03, 2008 10:45 pm

Do the engine revs pulse with the lights, or is it just the electical system thats pulsing?

If that is the case then I would suggest its a dodgy aux drive belt, or the voltage regulator in the alternator is going byebye.....Most odd..

If you have a multimeter stick it in the ciggy lighter carefully and tell us the voltage range its pinging around....

At idle I would expect to see between 12.5V and 14Vat the ciggy lighter...and it should be stable +-1.5V provided you dont rev the engine

Post by **alexperkins** » Thu Jul 03, 2008 11:27 pm

If you turn on the lights it will pulse yes

I have only just fitted a new auxilliary drive belt which is a little strange.

Will multimeter it tomorrow and let you know

Cheers