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Model specific boards => Golf mk2 => Topic started by: tobz. on 06 December 2004, 11:01

Title: What's this valve for??? (16v)
Post by: tobz. on 06 December 2004, 11:01
I changed the oil on my valver at the weekend and while I was waiting for the oil to drain I was having a poke around under the bonnet and found a broken vacuum line. There's a valve on the rear of the air box with a couple of large air pipes, an electrical connector and a vacuum line going to it. The plastic elbow is broken off the valve so the vacuum line is just hanging in space. What does this valve do and what's it called so I know what to order (I'm guessing I'll need a new one as the plastic elbow has snapped off).
It looks like the hot/cold air selector to me???

Toby
Title: Re: What's this valve for??? (16v)
Post by: Deefadog on 06 December 2004, 12:42
Sounds like the over run cutoff valve! does it connect to the intake above and also straight into the back of the airbox?

is this it - http://www.golfgtiforum.co.uk/index.php?topic=12817.10

If it is this valve just saves a few mpg by cutting the fuel off for a second as you go to idle, i think or somehting like that :)

I think it's about ?40 - ?50 at the stealership, or go down the scrapies :)

when this is
Title: Re: What's this valve for??? (16v)
Post by: tobz. on 06 December 2004, 12:52
Yep it connects to the inlet and straight into the airbox, can somebody confirm this is the overrun cutoff? Once I know what it is I can order a new one, I would have a look at the scrappies but must say I've never come across a 16v gti in any of the yards near to me.
Title: Re: What's this valve for??? (16v)
Post by: Volkswagavin on 06 December 2004, 13:01
For scrappies, try www.partsgateway.co.uk

You fill out a form with your car details and the parts you want, they email all the VW scrappies on their list and the scrappies email you with their quotes - just pick the cheapest and ring them with your card details and they post or courier it to you.  Sorted.

The one I've used a few times now is Volksapart - they appear as Volkswagenspares in their emails.
Title: Re: What's this valve for??? (16v)
Post by: Deefadog on 06 December 2004, 13:28
Well yes it is the over run cut off valve, did you read the post i added with pics?, it's all in there :)

radicoolvw scrapies should have them also, can't find the details now, but do a search on here, i have posted the details before ;)
Title: Re: What's this valve for??? (16v)
Post by: tobz. on 06 December 2004, 14:15
Cheers Deefa checked out the previous thread, mine looks ever-so slightly different but that's the fella I was talking about will check out the site as suggested by volkswagavin and see if I can find one. No rush as the car is off the road for the winter anyway.
Title: Re: What's this valve for??? (16v)
Post by: Deefadog on 06 December 2004, 14:53
nice one, the only thing it does is apparently save you a few extra mpg's! but throttle response is better with it disconnected :)
Title: Re: What's this valve for??? (16v)
Post by: Gambit on 07 December 2004, 08:50
your becoming good at this deefadog ;)
Title: Re: What's this valve for??? (16v)
Post by: Deefadog on 07 December 2004, 09:04
I know :) lol

It's amazing how much you learn when you good a sick car :)
Title: Re: What's this valve for??? (16v)
Post by: tobz. on 07 December 2004, 09:34
Got some responses through partsgateway and volksapart are coming up cheapest as predicted at ?20 delivered, looks like i'll go with them. One thought though, is this a part which is prone to failure (I've read other threads about people having problems with them) and therefore would I be better off just paying the price and going for a new one? My car drives so nicely through the gears, with the revs being exactly where you want them when you engage the next gear that I don't want to put an old part on that may change that.
Title: Re: What's this valve for??? (16v)
Post by: Gambit on 07 December 2004, 09:46
no the valves themselves arent prone to failure

what basically happens is that when your are above 2k and you take your foot off the accelerator the over-run cut off opens its airway. this now allows air to bypass the airflow plate, so the airflow plate to drop to its idle position and therefore less fuel is being used.

if you wire it all up and you dont like it. then all you need to do is disconnect the little wiring connector on the back left of the airbox. the little silver saucer thing. its this that receives the signal to open the over-run cut off