AUY TDI non start, Splutter & dies

[BeianM]

Hi I have a AUY TDI engine (VW) in a Ford Galaxy.
It will not start without a misfire & then dies.
Fault is g28 non coherent signal (crank sensor)
I changed with a new intermotor sensor, still the same
Has had immo off confirmed with diagnostics.
I shaved some of the old sensor to get it closer to the reluctor, no different.
Reluctor is on the rear crank main not part of the rear crank seal.
Sensor reads 2.5volt on all three connectors, Have read this is correct on another forum.
Continuity is good on all wires to the ecu plug.
Have by-passed the relay to the ecu to rule it out.
Good 12volt & earth to the ecu.
VCDS shows no sync of cam & crank sensors of course.
Next test is independent test of reluctor. Unless you can think of something els

[autoden]

On crankshaft sensor you should have a 5v reference disconnected. Have you checked?

[BeianM]

2.5v disconnected. There is 5v on the cam sensor however this gives a different waveform. I tried 5v on the crank sensor but it does not start at all. On a TDi forum someone claims to have measured the volts of a running car that is the same. Quite how bosch measure the waveform when signal & earth are connected together I don't know. I did try a second hand ecu but it was the same. I would have given up on this car but we just fitted a turbo to it.

[BeianM]

Have tried two different ecu now, same volts. Same fault! Anyone?

[autoden]

Then it has to be the vehicle. Disconnect and load test the wires.

[BeianM]

I have rewired to the sensor already. Going to try a genuine sensor rather than intermotor. Would help if we had another working car to swap parts from.

[autoden]

While you are at it, make sure egr is fully closed

[BeianM]

Interestingly, I had immo off the 24c04 in the ecu. but the immo light is on when I turn the ign. on (red led in top of drivers door) then starts to flash. The remote does not lock/unlock doors or set the alarm. The re-sync mode does not work eg. turn three times unlock but on second turn the front windows roll down as they should. None of the doors unlock remotely other than the fuel flap, although you can hear the solenoid working in passenger rear door. I removed the comfort unit under pass. seat. It is not corroded within & only small evidence of a couple of green pins. All cleaned up & still the same.

[johnnyh33]

i know it;s a renault issue but starter interfering with crank sensor? but renault or not they all use the same(ish) hardware.

could try a tow start, i.e. no starter motor interference.

[BeianM]

Thanks for the thought but it is automatic. I had hoped there was a immo boffin on here

[autoden]

Then check in control module live data, is immo on or off. Start authorised yes/no.

[BeianM]

Then check in control module live data, is immo on or off. Start authorised yes/no.

Here you go. Thanks for looking.

[BeianM]

So unless there is an immo guru here, this car is going for scrap soon. It has been on my drive for three months & no one here has been able to help. Shame it is a nice car

[Charli]

So unless there is an immo guru here, this car is going for scrap soon. It has been on my drive for three months & no one here has been able to help. Shame it is a nice car

go to the engine ecu,and check if you can read immo status
normally the cks has 3 wires(+ - sgn) so i don't understand why it has 2,5V on the 3 wires...

[BeianM]

go to the engine ecu,and check if you can read immo status
normally the cks has 3 wires(+ - sgn) so i don't understand why it has 2,5V on the 3 wires...

Previous post shows image of immo status
2.5 vol is correct for this car with sensor disconnected
fitted genuine new sensor from ford
rewired back to ecu
still says faulty sensor
Unclear if both 29f400 & 24c04 need to be set to immo off. (only did the 24c04)
It's not interference from starter.