When it cuts out, is there still an electrical supply available - IE warning lights / radio / car lights etc etc ?
I'm presuming there is because you say you can turn the engine over on the starter.
If it were an intermittent electrical problem I think you'd have noticed other symptoms too.
Not sure what to make of the vag-com errors - some of these could have been a result of the engine cutting out - rather than being the cause, so possibly misleading.
Sounds to me like a fuel problem, as if the engine is being starved of fuel.
When the cutout occurs, is it typically under similar circumstances - eg low engine rpm, or after engine has been idling for a brief period (such as waiting at a roundabout) ?
This is just a guess here - but perhaps the lift pump in the fuel tank is intermittent or failing. When that happens, then at lower engine RPM the tandem fuel pump (driven off the camshaft) hasn't got enough suck to pull the fuel up from the tank.
Not sure how you'd test it though.
On my Mk4 TDI, and I think this is normal, I always used to hear a rush/gurgle sound when I first turned the key, as the tank pump primed up. Do you hear that - or perhaps you used to and now you don't ?
I'm presuming there is because you say you can turn the engine over on the starter.
If it were an intermittent electrical problem I think you'd have noticed other symptoms too.
Not sure what to make of the vag-com errors - some of these could have been a result of the engine cutting out - rather than being the cause, so possibly misleading.
Sounds to me like a fuel problem, as if the engine is being starved of fuel.
When the cutout occurs, is it typically under similar circumstances - eg low engine rpm, or after engine has been idling for a brief period (such as waiting at a roundabout) ?
This is just a guess here - but perhaps the lift pump in the fuel tank is intermittent or failing. When that happens, then at lower engine RPM the tandem fuel pump (driven off the camshaft) hasn't got enough suck to pull the fuel up from the tank.
Not sure how you'd test it though.
On my Mk4 TDI, and I think this is normal, I always used to hear a rush/gurgle sound when I first turned the key, as the tank pump primed up. Do you hear that - or perhaps you used to and now you don't ?
