Engine cut out at 60mph

[Canonite]

Kudos for driving it to france in spite of an intermittent engine cut-out.
Hope you get it sorted out.

[Jar]

I owe you all an update and again thanks for all the replies. My wife took the car to Diesco in Ipswich for an injector leakback test. They said one of the injectors has a high leak back. It is now having a refurbished injector fitted and we will collect it later. I will take it on a very long (fast) run this weekend and unless you hear otherwise the very dangerous fault has been solved. If anyone else has this happen I would urge then to get it sorted asap. Loosing total power on a dual carriageway or worse on a bend in rural France is not for the faint hearted!

[Jar]

Not a happy bunny with Diesco. £240 later after replacing an injector they take it for a test drive and it is still cuttng out. So when my wife collects car they give her a bag with the synergy unit which I never authorised them to take off and say it was that and I probably need to change the other 3 injectors. So they bambozel my wife and I spend £240 on an injector which may have been leaking but wasn't the cause of the problem I asked them to rectify. I will send it to Rover Ron and whilst I doubt that is the problem I will als for his help and hopefully he can talk to Diesco

[Roverron]

Originally Posted by Jar

Not a happy bunny with Diesco. £240 later after replacing an injector they take it for a test drive and it is still cuttng out. So when my wife collects car they give her a bag with the synergy unit which I never authorised them to take off and say it was that and I probably need to change the other 3 injectors. So they bambozel my wife and I spend £240 on an injector which may have been leaking but wasn't the cause of the problem I asked them to rectify. I will send it to Rover Ron and whilst I doubt that is the problem I will als for his help and hopefully he can talk to Diesco

Unlike more recent diesels where stopping the engine when a fault is detected, is not an acceptable strategy*, on older systems it happens when the fuel pressure does not reach the expected level. If you tune the engine by any means - remap or any tuning box, clearly the extra torque requires more fuel so any weakness in the fuel supply and delivery system is highlighted.

There are many possible causes of cutting out ranging from a clogged fuel filter, the inevitable failure of the in tank fuel pump, intermittent under bonnet one, fuel pressure regulator with a leaking seal or clogged micro filter, faulty pressure sensor or faulty injector.
Injectors with leak back usually cause bad starting esp when hot and sticking needle valves usually produce a plume of grey smoke prior to the cutting out. This means it is often a process of elimination but any garage, should charge for their time, but not for parts that do not effect a cure.

The Synergy is blamed simply because removing it reduces the fuel demand: I've yet to come across a faulty circuit board even though I am happy to test them.

I am willing to speak to any garage if they phone me, but its not my job to teach them theirs nor get involved any any disputes.

There is a lot of info on my website here:

http://tuning-diesels.com/75Zt.R75serv.htm

Ron
* I heard that VOSA made VAG change from an engine stopping strategy to a limp home mode on some of their new common rail engines as this was happening whenever the ecu detected even a slight glitch with an injector. Apparently there was a bad batch of these but there was never any need to stop the engine (apart from reducing warranty claims ?)