Scirocco gtx high rev

Rajasgtx · Post by **Rajasgtx** » Fri Feb 08, 2019 1:12 pm

Hi everyone.
New to the forum.. look forward to hearing your feedback.
So i purchased a gtx last year .. in excellent condition only covered 110000 with full service history.. paid £1500.!!.

Now to the running issue. I have done
Full service
New throttle body
New distributor cap
Fith injector
Ignition coil
New timing belt and eater pump
Few other bits aswell.
It has a really high idle... when I first got it .. the idle was hunting and then once warmed up it would cut out. Wouldn't start again unless I pump the gas. And once started ... hunting again and then cuts out.
Since then i have had all the work done I mentioned above... got it back today and it has really high revs (around 2000 - 2500 consistently even when driving. The idle prob seems to have been sorted ... but now left with the high revving. I believe it may be down to the distributor and timing not being adjusted correctly...although I am no expert but since i have had the car you hear alot ...
Any help you guys can give me would be much appreciated.
Thanks

Rajasgtx · Post by **Rajasgtx** » Fri Feb 08, 2019 1:24 pm

Hi everyone.
New to the forum.. look forward to hearing your feedback.
So i purchased a gtx last year .. in excellent condition only covered 110000 with full service history.. paid £1500.!!.

Now to the running issue. I have done
Full service
New throttle body
New distributor cap
Fith injector
Ignition coil
New timing belt and eater pump
Few other bits aswell.
It has a really high idle... when I first got it .. the idle was hunting and then once warmed up it would cut out. Wouldn't start again unless I pump the gas. And once started ... hunting again and then cuts out.
Since then i have had all the work done I mentioned above... got it back today and it has really high revs (around 2000 - 2500 consistently even when driving. The idle prob seems to have been sorted ... but now left with the high revving. I believe it may be down to the distributor and timing not being adjusted correctly...although I am no expert but since i have had the car you hear alot ...
Any help you guys can give me would be much appreciated.
Thanks

mark1gls · Post by **mark1gls** » Fri Feb 08, 2019 5:59 pm

You could try and lower the idle speed using the screw at the back of the throttle body, you need a 7mm spanner to adjust it.

When you replaced the throttle body did you check the idle screw as the rubber O ring can go flat over time and let air in or slowly turn on its own and adjust the idle speed, if the car was hunting before it could be the anti stall devise was keeping the car running because the idle was to low.

Make sure the car is nice and warm before adjusting the idle speed, 950 - 1000 rpm is what you want but I find mine runs better at 1000 rpm as there’s less rattles in the car...

Have a look at this thread for where the idle screw is and the O ring as I’ve posted up pictures there.
https://vwgolfmk1.org.uk/forum/index.ph ... x-idle-low

What fuel are you using, super or normal unleaded?

Rajasgtx · Post by **Rajasgtx** » Sat Feb 09, 2019 1:59 pm

Thanks for your reply!
The idle screw is actually not even doing anything.... the screw doesn't even touch the throttle .. i think maybe the screw is broken ...I have been putting super unleaded . I had the distributor replaced 2 days ago along with the timing belt tensioner and water pump... I think the guy I took it too didn't adjust timing correctly so I will go to a VW specialist on Monday.. also is it possible there could be a vacuum leak somewhere...
Thanks

mark1gls · Post by **mark1gls** » Sat Feb 09, 2019 3:20 pm

Why did they change the water pump when replacing the cam belt?
The water pump is fitted to the front of the engine and runs from the alternator belt, it’s easy enough to change it without touching the cambelt, It’s only modern car which they recommend changing the water pump if it’s hidden deep in the engine...

You are doing the right thing running on super unleaded.

Try unscrewing the idle screw, it will just screw out and have a look at the o ring.

Rajasgtx · Post by **Rajasgtx** » Sat Feb 09, 2019 4:26 pm

They said it was leaking ... ok buddy will give that a go.
Thanks a lot for your time

mark1gls · Post by **mark1gls** » Sat Feb 09, 2019 8:44 pm

Ok if there was a fault with the water pump then that’s fine, I just don’t like to hear of garages just changing parts for no reason as a lot of places today have mechanics which can only find faults with a laptop and rely on the car telling them what’s wrong instead of using there knowledge and fixing the problem, they just throwing lots of new parts at it and hope that works...

Keep us updated on how you get on, we are always here to help and ask away if you wish to know anything.

Post by **GTXTRA** » Sun Feb 10, 2019 12:52 am

Is the idle stabilisation valve wire intact?

That can contribute to a high, erratic idle.

Rajasgtx · Post by **Rajasgtx** » Sun Feb 10, 2019 4:04 pm

I haven't checked to be honest... all I know is the accelerator cable is just sitting loose the screw doesn't even touch it .. I think it's broken..

blakey · Post by **blakey** » Sun Feb 10, 2019 7:52 pm

I think you may be mixing up the throttle stop screw and the idle control screw, the idle screw is the brass one which points towards the bulkhead on the throttle body.
Check out the info and link in mark1gls' post, the o-rings go flat with age and make it hard to achieve a consistent idle speed.

Turbogirlie · Post by **Turbogirlie** » Sun Feb 10, 2019 11:38 pm

Hiya,

On the rear of your throttle body is the Throttle Position Switch - it's a bugger to get to, so take the throttle body off. It's a micro switch which, if it isn't working properly will allow the car to idle at silly revs. I know as mine broke on my GTX. You can buy them complete with loom but someone's making money out of us as they want £50 for one. Any decent electronics engineer/minded person would be able to fabricate one for you for a couple of quid.

Good luck and enjoy your GTX!

Cheers,

essextom · Post by **essextom** » Mon Feb 11, 2019 6:38 am

Theres a brass idle screw (hex head) on the rear of the throttle body, unscrew it and check the condition of the o-ring, if its hard replace it. i replaced mine as it had a dodgy idle and made a huge difference.

Rajasgtx · Post by **Rajasgtx** » Mon Feb 11, 2019 4:02 pm

Thanks guys for all your help .. I will try this method .. I'll let you know how it goes

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