VR6 stalling/cutting out intermittently

[lewvw 10]

On saturday morning got about 50 metres from my house and the engine cut out very sharply then wouldn't restart.

Pushed it home and tried again 20 mins later and it started. Switched off and it wouldn't restart. Scanned it yesterday no codes (apart from crank sensor but it wasnt running). Battery went flat from cranking so jumped it tonight and it started but idled at 2000rpm until warm but won't drop past 1500. No codes when running. I have changed the isv damper chamber and cleaned out the isv about 2000 miles ago.

 

This sounds isv related though does it not?

[vw rule 19]

Hello mate,

yeah it does sound like the idle control valve is playing up,

these tend to give up the ghost when there old and can have heat damage from being too near the cylinder head for 80.000 miles or more,

which can course the inner valve to become stuck open or closed, which in turn will course cutting out or erratic idling.

You can clean out the inside of the ilde control valve but it may only last a wile before it's coursing the idle problem again.

Best bet is to replace with new, I think they are around the £50.00 mark ?

 

Have you checked to see / hear if the fuel pump is working when ever your VR6 doesn't start up ?

(There should be a light buzz from under the car as soon as you turn the ignition on the fuel pump should prime the system up ready, this you should hear)

 

Have you got an alarm / immobilizer ?

Not so much the alarm but the immobilizer normally cuts power to the starter motor, fuel pump, and on some the ignition coil pack as well,

and is armed / disarmed by the alarm key fob.

If you've got a after market security system which has been on the car for some years the alarm control unit can sometimes burn out,

on the circuit to the fuel relay or ignition coil pack which can course the car not to start sometimes or not start at all.

I had this on my Corrado where it would start up some days then it wouldn't,

on the days when it didn't start I tried to hear for the buzz from the fuel pump but heard no noise,

I found the alarm control unit under the dash drivers side,

and traced it's wiring to the fuel relay, tested it for power and there was none,

so cut the wiring out and connected it back up to the relay as it was before the alarm was fitted and the car started up fine.

I'm not saying this is the fault on yours but don't rule it out.

 

You mentioned the crank sendor these work off the crack shaft pulley or flywheel it's self,

the crank sendor is like the ABS speed sensor it measurers / pulsates off a set of teeth so it's able to communicate with the ECU,

and tell the spark plugs / HT leads when to fire, if the crank sendor is not working at all then your car WILL NOT START.

But you said you've got no fault codes stored in the ECU memory as you say you've carried out a scan, so not sure.

I know on some vehicles when the crank sendor is on the blink they can course the rev counter needle to move slightly,

when you turn the ignition on and so don't store a fault code.

 

Coolant temp switch can play up but your car should still start up though and it would run rough.

 

Check the main wirring loom as you could have a broken wire some where,

what I mean is wiggle the loom around in case it courses the car to cut out, mainly the loom in the engine bay.

 

I hope this helps, hope you get her running spot on again :salute:

 

Si :thumbleft:

[lewvw 10]

Yeah i'm thinking isv, can't see it being as cheap as £50 though :( cheers for the comprehensive reply.

[vw rule 19]

No worries :thumbleft:

[GlosterOx 0]

I think I've got a 2nd hand ISV somewhere Lewis if you want to try it?

 

Ian.

[CazzaVR 0]

Also worth cleaning the immobiliser plug with contact cleaner/WD40. Just remove the driver undertray, trace the black wire from the immobiliser ring (around the ignition barrel) down to the little black box. The plug is small and black. Remove, spray, replace, repeat. Only takes 5 mins.

 

Could also be the ignition switch or the MAF, although the ISV sounds like the chief culprit.

[lewvw 10]

This ISV has given me trouble before! I'm definitely turfing him out! However at £268+vat trade from TPS I think i'll give Ians a try. Cheers Ian :)

[vw rule 19]

Have a look on Ebay this is the item number 260702620389

 

Various idle control valves for Corrado VR6 all new ranging from £30.00 up to £70.00

 

I thought you could get one for around £50.00 ish, have a look mate

 

 

Si :thumbleft: