Hi,

my garage cleamed my throttle body after fluctuating revs at idle about a month ago, they adapted the throttle body using a BOSCH tool. They said it had the correct software to work on VW group cars, The car had to have a new brake pedal switch today and this fault was in the error log. The car revs bounce up and down until you hold the accelarator pedal down for a couple of seconds, it does not do it all the time once every two to three weeks. The engine is a 1.4 16v 100bhp I have had the egr replaced coolant temp sensor done and its had a new thermostat, also had two faulty engine fuses replaced. Im thinking of buying a VCDS reader and the vw software for my laptop where is the best place to buy from for a 2001 model hatchback, and I have searched the forums but no one every seems to post a a final update or solution. I will when I get to the bottom of it this car is starting to frustrate me now, many thanks for any help and advice.

I was going to say air leak somewhere in the intake until I read the once every to or three weeks. I'd expect an air leak to cause problems all the time. It would probably help a lot if you knew what fault codes it was throwing up.

Have the tried resetting all learned values? Could be some help to you.

Search the forum but it goes somthing like this.

Turn everything off on the car, fans to zero, radio off etc..

Remove the earth lead from the battery for about an hour or so.

Connect the battery after that and start the car, do not touch any pedals or anything els untill 30 minutes have passed.

Thats what i remember anyway. Google it or search the forum

Try my post on restting the ecu........

linky here..

http://www.briskoda.net/forums/topic/201016-how-to-reset-the-engine-ecu/page__hl__%20how%20%20to%20%20reset%20%20the%20%20ecu

Hi,

Thanks for all the replys will try the ECU reset the next time it starts to hunt. I have found a new throttle body for £246 on GSF parts so may bite the bullet and buy one in the new year as thats when I get my bonus at work. If its an air leak where do I look and could it be a faulty air pressure sensor. I thought if it was the throttle body it would do it all the time.

To be honest I spent 6 months with my old 16V trying to find the cause of this fault as i had similar symptoms. But with mine i found that after short/sharp journeys it was more likely to happen, making me believe its a gasket or some kind of air/vacuum leak.

Good luck with finding the fault, i would like to know how you get on

Thanks for the reply I have found that I have a mionr leak on the front exhuast flex and a minor oil leak at the bottom of the engine will have to get these sorted after xmas now. I will keep it updated if I ever find a fix, before I sell it as any more problems its time it went and im thinking of getting a new honda civic.