Need help asap with a non starting ZT diesel please!
 

As above I need some help with my son-in-laws non starting ZT diesel please.

The car has been running fine up until xmas eve.

He used it as usual to commute to work and back, all was good. Parked up on the driveway about 2pm. At 6pm went to go out and the car would not start.
When the emergency crew arrived (Me & the toolbox), I checked the battery, fuel pumps, (Both running fine) all was good. I then removed, cleaned and replaced the cam sensor, to no avail. As it was getting dark I said I would return after boxing day.
Upon my return on the 27th, the car would turn over, but not fire up. I connected the laptop with TOAF and looked for logged faults (One about RPM Sensor, Cant remember the code, Faulty Crank sensor??) and then read the "Live Data" from the engine to make sure the low pressure fuel supply was ok, 3.5 bar was shown.
I gave a squirt of easy start, and it fired up, but then died as few seconds later.

I returned home, confused and then read various threads on here. Particularly THIS one.
As a result, these are the things checked thus far;

The plenum is clean and dry. Disconnected the battery, then ECU and checked for "tidelines" and water damage, nothing apparent.

Starts on easy start, but only runs for a few seconds, then dies.

VBattery measured at the crank sensor, when disconnected and key in pos 2, 11.99V,

3.99V Measured at the low pressure sensor on top of the fuel filter (Complicit with TOAF reading 3.5bar),

HP Rail sensor measured at 0.51 (Key pos 2) and 1.25V when cranking (Complicit with seeing at least 250-320bar fluctuating on TOAF when cranking),

No signs of any diesel leak anywhere, particularly around injectors,

Clamped each leak off pipe between injectors 4-3, 3-2, 2-1 etc when cranking, no fire,

I assume the immobiliser etc is ok as the car fires on easy start?

How do I test the Crank sensor?

I have had the battery on charge since this morning, and when charged, I will refit and do a leak back test. I am assuming that they will be ok though, as when clamped between pipes and cranking, it never tried to fire, at all.

Anyone got any further ideas? Any help/advice is greatly appreciated. :D

Can you see the rev counter needle move at all when you crank it over? If not it could be a faulty crank sensor or wiring to it.

The rev counter needle moves up to about 200rpm when cranking. But still not firing on a fully charged battery.
Leak back test also performed, not a drop from any of the injectors.

As you are getting a good high pressure fuel reading the only thing that seems to be missing is the signal to the injectors to start working.

Maybe a bad connection from a sensor to the ECU.---:icon_question:



Easy start will fire up every time. Immobiliser not involved.

This just sounds like the problem I had and BigRuss suggested the solution. Unbolt the under the bonnet fuse box and pull out each connector in turn and use a contact cleaner or push the connector in and out a few times.
Also worked for another member about a month ago.

I have no idea so my idea could be a red herring. Is fuel being pumped, not blocked anywhere. I know you said pumps run

macafee2

Check all of the fuses in the engine bay fuse box...

Thanks for the suggestions, thus far folks. :bowdown:

I am off to my son in laws now armed with a spare engine bay fuse box, fuses, relays and fuseable links.

I will report back later......

Sounds like injector load drop to me ;)

I can test the ECM for you :xmas-smiley-008:

Brian :D

Thanks for the offer Brian. Much appreciated :xmas-smiley-008:

Just returned home.

I removed the fusebox and cleaned every connection with contact cleaner. I then checked every fuse and fuseable link, all to no avail.

I then checked the continuity on the loom from the ECU to the injectors and all was fine.

I then re-ran my original tests and whilst measuring the cam sensor, realised I am only measuring Vbatt on the yellow wire with the cam sensor disconnected. When connected, I am reading 0V. Am I correct in thinking that the cam sensor has failed, short and is pulling the voltage down to ground? :duh: