cdti starting problem, and now not starting

[Mike Noc]

And if you have an automatic gearbox you can get EP displayed instead of which gear you are in.

Another symptom can be the LP fuel pump/s don't run once the key is turned. This can be due to either a faulty ECU, or break in the control voltage wire between the coil of the fuel pump relay and the ECU.

[andyorkney]

Originally Posted by Mike Noc

And if you have an automatic gearbox you can get EP displayed instead of which gear you are in.

Another symptom can be the LP fuel pump/s don't run once the key is turned. This can be due to either a faulty ECU, or break in the control voltage wire between the coil of the fuel pump relay and the ECU.

Both in tank and under bonnet pumps running fine, fuel is getting to the HP pump and can hear it hissing through the High pressure pump as it primes. It is the Auto gear box, but gear selections showing correctly on the instrument display. I'm guess that because the rev counter is moving when I turn engine over then crank sensor is apparently working too?

Anybody know symptoms of problems with HP pump actuator not working correctly?

[andyorkney]

Originally Posted by FrenchMike

I think in case of fauly ECU,the oïl warning is absent when ignition is set

Oil warning lamp definitely there. Just wish I had access to T4 or equivalent...

[FrenchMike]

Originally Posted by andyorkney

Anybody know symptoms of problems with HP pump actuator not working correctly?

If your HP sensor measurement is correct ,forget it

[hogweed]

Thing I found is that, if you try to use logic (even educated logic) with these motors, you can drive yourself mad – there is SO much that is simply beyond the ability of even a very competent mechanic to resolve.

I had a similar problem to yours a few years ago, and went to a highly-recommended “diesel specialist”, who ended up replacing all sorts of things, charging me nearly £400 – and the problem was still there.

Eventually I took a chance on sending my ECM to Marinabrian for exchange, despite the fact I was convinced it wasn’t the problem – 3 days later, car back on the road, no problems in the 3 or 4 years since.

Think of the hassle of changing all the different coded bits… and, if you change the ECM etc, are you REALLY going to be sure it hasn’t been for a dip at some stage in its life, and have an intermittent fault too?

Originally Posted by andyorkney

Oil warning lamp definitely there. Just wish I had access to T4 or equivalent...

There is no equivalent

[andyorkney]

Ok I replaced the wiring loom from ecm to engine sensors yesterday, as I had suspicions about crank sensor wiring. But no joy.

So tonight I have replace the ECM and EWS from donor vehicle (rip!) and swapped the key chips and voila started first time and without issue. So I know that it was the accidental bath that the ECM took many months ago had caused problem, though I still wonder if the suspect crank sensor wiring might have contributed.

Anyway I've learned lots about how the diesel 75 is put together. Thanks to everyone whose offered suggestions and ideas, they've all helped. Now of course I'm looking at diagnostic solutions so can try to ID these sort of issues earlier. VT4 or TOAF. VT4 may not work now well now that I've swapped ECM and EWS as VIN won't match....

And of course, newbees and everyone who doesn't do it regularly, check your Plenum!

[FrenchMike]

Glad for you ...at last

since the begining ,plenum drains have caused thousands issues like yours ...
really bad design

[binraider]

For future reference - my non-starting CDT was down to two broken wires under the main fuse box in the engine bay. My pscan reported a failure with the high pressure diesel sensor (amongst other things sensor related), but i swapped it out for the one from my other cdt and the fault remained even though the other car has no issues.

There are a few wires under the fuse box that are inexplicably thinner than most of the others - in my case the two wires at fault had "flat spots" where the plastic sheathing was still hanging on but the wires inside had seperated. Once i soldered them back together the car was back to normal.

Marshall

[hogweed]

Originally Posted by binraider

For future reference - my non-starting CDT was down to two broken wires under the main fuse box in the engine bay.

Yes, I believe that's a known issue - good to be reminded every so often, as I think most of will tend to look suspiciously at components first rather than actual wiring...

[Greeners]

The big problem is if the car has lost the inspection panel in the wheel arch at some point and the water and dirt gets directed straight under the fuse box on that part of the loom