6n2 gti Idling problem

[ben_gti]

Hi Guys n Girls,

This is my first post in this forum and unfortunately its bad news.

I have only owned the car for about a month and this random problem has started.

When you start the car the idle jumps between 800 – 1200rpm in a bouncing motion for about out 15 secs then it settles down. But when you tap the accelerator pedal it starts again. When you try and drive off you have keep the revs really high in order for it not to stall. Once you have driven down the road it goes away and everything is how it should be.

It doesn’t do it all time. Sometimes I can go for a few days without it playing up. It doesn’t seem to matter whether you start it in the morning or when the engines warm.

I have taken to a garage and had a full service done but they can’t pick it up on vag com. They said they can only fix it if it’s doing it when I take it in. But every time I take it to the garage it behaves its self.

It’s a Polo 1.6 gti year 2000 on 122000 miles.

I hope some can shed some light on it.

Cheers,

Ben

[bstardchild]

Sounds like idle control circuit is gummed up and the ECU is trying to control it and over compensating hence the hunting - throttlebody could probably do with a good clean to get any carbon or oily residue of the butterfly and air path

[ben_gti]

Thank you for getting back to me.

I will let the garage know about the idling circuit

What is a good way to clean the carburettor or is that a job for the garage?

Cheers,

[bstardchild]

Thank you for getting back to me.

I will let the garage know about the idling circuit

What is a good way to clean the carburettor or is that a job for the garage?

Cheers,

Buy some carbcleaner - should be able to get it from Halfrauds or similar

Remove airbox
spray inlet and throttle butterfly with carb cleaner and wipe away carbon/oil residue with clean lint free cloth
Spray on Toothbrush if you need to scrub and clean any stuborn bits

*should be able to open butterfly by hand (it's fly by wire so I'd take advice from others* who have done it - I haven't needed to yet) and clean the back side too

In the throttle body it self there will probably be some drill holes above and below where the butterfly is - give these a good old jet of carb cleaner - should get rid of anything blocking or partially blocking the pathways for idle air control - I'm not speaking from experience just general 6N stuff rather than 6N2 GTI

[ben_gti]

Good stuff. I will give it a go over the weekend.

Thank you for the advice!

[funlovincriminal]

I had very similar idling problem,

Firstly got the coilpack replaced & was sound for a while, but then started playing up again & found it to be a split a lead, got all leads replaced & it now runs perfect.

[ben_gti]

Ok that's interesting. Which leads are you referring to? The HT leads?

[funlovincriminal]

Ok that's interesting. Which leads are you referring to? The HT leads?

Yes HT leads, got them replaced & the idling problem was history. Wasn't too much of an expense too, & coilpack was only £30ish.
My gti always felt & sounded like it was going to stall, but very rarely did. I always found the problem to be worse in damp/ cold weather.

[ben_gti]

This doesn't seem to matter what the weathers like but it’s driving me mad!

I think the best thing to do is change the coil pack and ht leads and give the throttle body a good clean at the same time.

I just had quick look at the coil pack, looks like 3 bolts and a cable connection. I take you have to disconnect the battery before doing this job?

Thanks,

[bstardchild]

This doesn't seem to matter what the weathers like but it’s driving me mad!

I think the best thing to do is change the coil pack and ht leads and give the throttle body a good clean at the same time.

I just had quick look at the coil pack, looks like 3 bolts and a cable connection. I take you have to disconnect the battery before doing this job?

Thanks,

Clean the throttle body first - then look at leads and coild packs after if it doesn't do the trick - cleaning a TB is gonna cost you a fiver for the cleaner and if it doesn't work I'll be surprised

I bought my new leads for the GTi from VW and they weren't cheap - also had to be ordered in special (unless I wanted black ones instead of red - which I didn't)

[ben_gti]

I will give it a go and report back on how I got on.

Thank you for all the advice guys!

[ben_gti]

Hi Guys,

Just a little update on this.

Turns out it was a dirty throttle body. I cleaned it out with carb cleaner and cleaned both sides of butterfly. I also cleaned out the air box. It was very very dirty and now it runs like a dream. Thanks guys!!!!!