cdti starting problem, and now not starting

[andyorkney]

Ok I've been reading in various forum and trying out many many things to identify the problem with my diesel 75. Fuel pump in tank had been an issue, replaced. UB pump is also new. Plenty of fuel flowing though the filter. All new filters. injector leak back tested and all good.

So problem was poor starting, but discovered that if leave key in ignition and on for 4-10 mins then starts without a problem. I'm not entirely sure that I'm not conning myself, but also seemed that the pitch of the UB pump would change and at the change in pitch car would start. Garage has put on general OBD2 scanner but not identified any problems, he reset the codes. I've got hold of scanner and not a single fault code showing.

Friday evening half a mile from home my 75 cut out and refused to start (has occasionally cut out, seems to have been doing this if I started it too early in the wait for 4-10 mins cycle). I coasted home. The following morning it started and I managed to put on my drive to begin further testing of sensors etc. Since then the car absolutely refuses to start.

The ECU has been wet once during last summer, hadn't checked plenum, but has been dry since and fault has occurred long after. I am however beginning to suspect the ECU. I've replaced the crank sensor and the cam sensor (used parts). replacing the crank sensor seemed to cure the poor starting for about 2 days but then reverted back to the 4-10 minutes wait to start routine.

I'm considering purchase of engine bay wiring loom(£20) and used ECU-immobiliser-chip pack (£125) to see if that resolves the problem. Anyone out there had an experience similar, or might point me in direction of something I haven't tried? Thanks in anticipation!

[Stickman]

You need to get it on a t4 buddy before throwing any more money and parts at it
Regards
Chris

[andyorkney]

Hi

I'd very much like to get the car on T4 test but don't know where to go to get it plugged in. The only place that I know that might have T4 gear in my area is Hunters Landrover, but I've been ripped off by them in the past so won't touch them. Any ideas how I can get T4 diagnostic done, can the gear be bought on line?

[FrenchMike]

Originally Posted by andyorkney

Hi

I'd very much like to get the car on T4 test but don't know where to go to get it plugged in. The only place that I know that might have T4 gear in my area is Hunters Landrover, but I've been ripped off by them in the past so won't touch them. Any ideas how I can get T4 diagnostic done, can the gear be bought on line?

Hi,without T4,you can carry out some essential measurements(preferably when at fault):

http://www.the75andztclub.co.uk/foru...d.php?t=109615

Good luck

Mike

[Greeners]

If the ECU has been for a dip in the past, there's a good job its now failing Your closest T4 chap is Phil in Olney, or Marinabrian or BigRuss via post.

[andyorkney]

Originally Posted by FrenchMike

Hi,without T4,you can carry out some essential measurements(preferably when at fault):

http://www.the75andztclub.co.uk/foru...d.php?t=109615

Good luck

Mike

I've conducted all these tests over the weekend and all look good, thats kind of why I'm leaning to ECU fault. ECU is clean as whistle though, none of the mineral deposit damage that water damage often shows... frustrating!

[FrenchMike]

Originally Posted by andyorkney

I've conducted all these tests over the weekend and all look good, thats kind of why I'm leaning to ECU fault. ECU is clean as whistle though, none of the mineral deposit damage that water damage often shows... frustrating!

Before sending it to a ECU guru,try to clean the PCB with a little bush and
isopropyl alcohol ..

any corrosion conducts more or less electricity ,no good in MOS circuitry

Mike

[Greeners]

well if it's clean inside thats good news

Check the condition of the glow plug relay that lives below the ECU, and the EWS module that lives at the bottom of the A pillar drivers side. Not unknown for that to get wet wither

[andyorkney]

Originally Posted by FrenchMike

Before sending it to a ECU guru,try to clean the PCB with a little bush and
isopropyl alcohol ..

any corrosion conducts more or less electricity ,no good in MOS circuitry

Mike

Hi Mike, that was one of my first jobs. I've a big tin of the stuff I use when clearing up electronics and in water damaged iPhones etc that I fix. Another reason that I'm suspecting the ECU is that while the software ands OBD2 lead I have reliably detect revs as I attempt to start the 75, and the throttle position, the fuel pressure is not always reported, though the voltages measured at the rail sensor map out as they should, though it could be that there's a wiring fault too. But the fact it would start once it had "warmed up" with ignition turned on points me in that direction too.

Folks, I am right in assuming that if I buy used already paired ECU, immobiliser, and key chips then if is ECU fault replacing these matched items should work?

[FrenchMike]

Originally Posted by andyorkney

Hi Mike, that was one of my first jobs. I've a big tin of the stuff I use when clearing up electronics and in water damaged iPhones etc that I fix. Another reason that I'm suspecting the ECU is that while the software ands OBD2 lead I have reliably detect revs as I attempt to start the 75, and the throttle position, the fuel pressure is not always reported, though the voltages measured at the rail sensor map out as they should, though it could be that there's a wiring fault too...
?

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