Corrado VR6 intermittently cuts out dead... help!

Hoping that someone can help me, as this has got me completely baffled...


1994 Corrado VR6 intermittently cuts out for no apparent reason: No misfire, stutter or change in engine character before it cuts out - just an instant stall, dead.


Fault can happen when car is sat idling or when it's being driven, more likely to occur when car has been running for more than minutes and warmed up.


Car runs perfectly outside of this fault, it's just sailed through it's MOT, emissions readings are spot on - car behaved perfectly through it's test, but stalled on it's way there and on way back after.


When it cuts out there are no dash lights illuminated: oil pressure, coolant, brake, ABS warning and ignition lights all stay off.


Mileage and clock stay constantly on when fault happening and don't flash off or disappear/flicker as fault happens.


Car can stays 'dead' for a few minutes, re-trying to start it does nothing - no dash lights illuminate and no sounds from any relays. Other times it re-starts straight away.


Car has a Scorpion 1218T alarm, which still works perfectly throughout the fault - car will arm and un-arm as normal, locking all doors and illuminating the separate dash alarm LED.


Arming and un-arming the alarm does not reset or clear the fault - car stays in dead state even after this proceedure... until car decides it's time to start again.


There are NO faults on VCDS when scanned (apart from the normal crank sensor G28 fault code '00513 03-00 no signal' when any VR6 engine is off, which clears and stays off once started).


I've recently changed the ignition switch 6N0905865 twice (Meyle) & both the ecu relay 109 and fuel pump relay 167. Also been through all the fuses. No change.


I removed and checked the cars ECU yesterday, to look for any damage or burns on the main PCB - all looks perfect.


In the 19 years I've owned this Corrado (and 32 years of VW ownership) I've never had a fault I can't rectify... until now.


Any help or advice would be most appreciated.

Well as you know the ECU relay at position 3 is a notorious failure. When it cuts, have you been able to see if the rev counter drops straight to zero with the engine still turning with the cars inertia? I would also find the immobilisation paint and temporarily bypass them one at a time to see the effect whilst still maintaining theft protection.

Thanks for the reply Crasher, much appreciated.

I can't recall if the counter drops straight to zero when driving, but I'll take it for a short drive this week and check if it does - would this possibly point to something else?

Will also go through alarm immobilisation points and do what you've suggested.

Car is a 1994 with an AG ecu, is the factory immobiliser in the ecu on these as it doesn't have a coil reader on ignition barrel?

Many thanks.

Only 95 model year cars from VIN wvwzzz50zSK000718 had a factory fit immobiliser so ECU 021 905 258 CP

Sorry for the delay Crasher... think I've sorted it!


Had a good going through the wiring under the drivers side of dash, all okay.


Checking behind the fusebox I found a plug not quite seated correctly, think it was plug G1 or G2 (tricky to see behind in there).


Since clicking it back in correctly (& making sure the rest are seated tight) it's been as good as gold... even feels better to drive.


Thank you for your time and knowledge on this issue...


Cheers mate.