mk3 16v cutting out after warmed up randomly

[fingermouse1911]

Hi,

I've just bought myself a nice Gti 16v, its a lovely car apart from one minor detail.  It's not reliable.  I bought it becase Golfs are known for reliability.

After the car has warmed up it can cut out at any time, but never when cold.  I've had a new distributor fitted, as the hall sensor had snapped off.  New coil as i've heard that the aftermarket one that was fitted can send too much resistance to the ECU.  I've had the ECU checked, but this came back fine.  Last night I pulled the fuse number 30, as I think it could be the cause of the problem.  Fuse 30 is dedicated to powering the ECU.

I am wondering if a combination of rising cabin temperature and relay temperature after a long period of operation can cause the symptoms to manifest themselves.

Well its my last resort up to now anyway!!

Any comments on this issue greatly appreciated  

[8vgti]

Do a search for similar threads on 'stalling' as there have been a LOT of responses to this type of problem.

[8vgti]

Try this.....

http://www.golfgtiforum.co.uk/index.php?board=8;action=display;threadid=2080.

[fingermouse1911]

Aye, I've read them just now.  I changed the relay and have been driving it all night just to test it.  I thought it may be heat related as it only happens when warm so I tested this theory tonight.

I took it pretty much flat out (142mph ) and then drove round my home town pottering around at 30mph.  Normally the heat from the speed would have an adverse affect, it didn't.

So I tried the second test.  I came home and parked it up, left it for 40 mins and it wouldn't start after that time.  This is all a very expensive business, I had pay 80 quid just so somebody could tell me my ECU was 'OK'.  It seems heat and time related, it's really strange.  It has to be going a good while before it cuts out.  Also it can sometimes splutter for a second under acceleration.

If my heat related theory is correct, what would I look at?  Is there a temperature sensor or something else that can be affected by heat that I should look for.  Am I barking up the wrong tree?

Please please..I need help!!!!!!!

Thanks

Simon

[fingermouse1911]

Sorry for to include some key information.

When it dies, the rev counter drops to zero whether the engine is spinning in gear or not.  It's definately gotta be electrical

Si

[fingermouse1911]

well I finally found my problem... my cutting out was due to a faulty engine speed sensor (crank).  I had it installed today.... fixed the problem.

It's basically a f**king magnet and 2 wires that cost 120 quid... My mountain bike speed sensor works in exactly the same way, but was 12 quid!