No no no no. Everything was going so well.

New car (MK1 Oct VRS), running great.

 

Noticed ever so slight lumpiness so thought Id clean the throttle body...

 

Cleaned and bolted back on...now!!!!

 

Revs like absolute crazy on idle.

Fluctuates from 500rpm- 1400rpm as if im pressing the throttle and releasing continually.

 

Please help what this could be?

 

Im sad

The 1.8T throttle body stepper motor needs to realign itself.

 

Open the bonnet.

 

Turn the ignition on (but don't start the car)

 

Wait about a minute

 

 

You should hear the throttle body cycling, it should take about 10 seconds

 

After it's finished start the car and all should be well in the world again unless you've damaged something whilst cleaning.

Edited 10 March, 201511 yr by Sheldon.Cooper

Are all the pipes back on correctly and tight?

Sent from my Galaxy S5

Has to be one of the above if linked to the throttle body. Erratic idle could be unmetred air entering the system so check your putting back together. If those don't solve it I'd suspect maf and you've had one of those weird coincidences. Could have been the maf in the first place and it's just given up now. Try the above first though.

From some googling I think it may need realigned.

 

Idle before trying to clean was fine, as soon as I clean and put back together its awful!

 

Would this be a common issue for a TB needing realigned?

If you unplugged it when cleaning yes, if not you can usually get away with it.

Right on thanks, I'll investigate tomorrow

Cool, then enjoy the benefits, for such a small job the payoff is pretty big. Mine wasn't that dirty but running was still much improved.

I just hope a simple alignment will sort it. I only wanted to clean the darn thing lol

I know, simple jobs becoming a nightmare is my favourite trick. Hope it sorts it, should do.

on polo's, you need vagcom to reset t/bs

Tell me about it yellowcar!'

And thanks Sebring, hopefully that will sort it...

I left mine plugged in...I didnt even unbolt the throttle body

It will settle down after a while,

 

it just needs to relearn its adaptions now its all nice and clean,

 

I just started mine and left it to idle until it got warm and after about 10 minutes it settled down

If thats right volvomeg, Ill buy you a virtual beer. lol

Its a bit scary leaving it to idle whens it literally about to stall then it revs up!!!!

The 1.8T throttle body stepper motor needs to realign itself.

 

Open the bonnet.

 

Turn the ignition on (but don't start the car)

 

Wait about a minute

 

 

You should hear the throttle body cycling, it should take about 10 seconds

 

After it's finished start the car and all should be well in the world again unless you've damaged something whilst cleaning.

 

 

Old wives tale that one.

 

Yes it makes some noises but it doesn't do anything as such.

 

As above if it ain't been re-aligned with VCDS it will sort itself after a few mintues of erratic idle.

I take it the gasket was ok when you refitted it or did you not remove it from the car?.

Thanks David, reassured slightly now.

I did check the gasket Phil, it was still secured to the body itself with no signs of perishing. For the sake of a few quid i may replace it anyway

on polo's, you need vagcom to reset t/bs

As sebring says, you need to use vagcom. This is an issue specially with the 6N/6n2 polo valvers, it's quite common and I had it this issue too.

 

I  know some who have forced open the butteryfly only to find it had the irratic idle after. Knowing this I left the TB on and got someone to press the throttle to open the butterfly and cleaned it that way.

 

Try the gasket and then find someone to reset the TB using vagcom, I think that is going to be the only way.

Edited 11 March, 201511 yr by DeanVRS20VT