MK4 Stalling/idling problem

TommyG 69 · 19-11-2007,01:32 PM

Hi guys,

On saturday i test drove a 2000 GolfMk4 1.4 and it drove perfectly. One thing i did find slightly odd at the time is that the rear window heater was on, but i didnt think any more of it as it was so cold.
I bought the car yesterday. Down he road i turned the heater off as i didnt want to burn it out and sortly after the car stalled when i stopped at lights. This proceeded to happen another 5 times over the course of the day. It mostly happened when the revs went from high, and then by dropping the clutch dropped straight downpast "idle" to like 200-300 and then cutout.
Thankfully, it always started up again straight away.

I have spent hours searching these awesome forums for help. I am coming to you guys for some more specific advise as i am not the most technically minded with cars (and that may be overexagerating

)

I read on the forum (sorry, cant remember who from) that the heater would boost the signal to the ECU or something simular. This appears to be he case with mine. Obviously i dont want to just run with them on the whole time,so how can i go about finding and fixing the route of the problem?

A couple of things:
-The car as standard idles very smoothly at 800-900rpm
-It is low mileage 40k, full written service history and last service was 2k ago.
Any help would be very much appreciated. I have saved up for a couple of years for a nice golf and am very excited about joining the family; I am just totally gutted that it looks like i have been tricked into buying a kipper..

Please

Many thanks in advance,

Tommy

TommyG 69 · 19-11-2007,01:40 PM

Haha loving the title under my name. Quite apt

**Crasher** · 19-11-2007,02:25 PM

The throttle body needs to be removed and thoroughly but carefully cleaned internaly with a stiff nylon brush and aerosol carb cleaner. After it is refitted it should be re-adapted to the engines computer using a diagnostic system such as VAG-COM.

TommyG 69 · 19-11-2007,02:53 PM

Since i am not the person to do this, is this the sort of thing that most good garages should be able to do, including the VAG-Com?
What sort of labour time is to be expected?

Thanks

**Crasher** · 19-11-2007,03:33 PM

It takes about an hour to do the whole job so except to pay around £60 to £70. Any decent garage should be able to do this for you.

TommyG 69 · 19-11-2007,05:46 PM

What about the idle control valve dude? Maybe it needs cleaning or there is a fault with it?

The rear window heater idea has gone out of the window as it now cut out with it switched on..

I have just been out for an approx. 8-mile drive.
I had my full lights on for the first 4 miles - it cut out at traffic lights 4 times.
On the way back i left my lights off, and it didn’t cut out at all.

Would that point to anything, or maybe just a coincidence?

**Crasher** · 19-11-2007,06:07 PM

The idle control valve would be relevant if it had one, dude! The idle is controlled by a stepper motor in the throttle body which has control of the throttle valve (butterfly) when the throttle is closed.

TommyG 69 · 19-11-2007,07:24 PM

Oh okay, fair enough. The only reason I mentioned the idol control valve is because that is what both the AA and my local garage told me that it would be, they were "90% sure".
No disrespect intended, just trying to gather as much intel as possible for when i take it in.

Any idea on the random lights/cutout combo?

**Crasher** · 19-11-2007,09:08 PM

No disrespect taken, made me smile old boy! It just shows you that most breakdown people and other experts really haven’t got a clue. One of the perils of trying to cover all makes and models, give me some Jap rubbish or something to work on and I am lost.

TommyG 69 · 20-11-2007,12:25 AM

Sweet. It is deffinitely hard to know who or which people to trust in this, esecially as for me it is a new car with fresh problems.

I am going to take it in this week and ask to get the throttle body cleaned and ECU adapted as suggested.

Ill let you know how she turns out. Thanks, dude