2.0tdi crank but no start with no faults

[waynesturbo]

I currently have a 2.0 tdi T6 in the workshop that will not start. It had a Egr fault once but did not return. I've checked everything I can think of and was looking for some direction. On crank it has good fuel pressure, air flow, rpm signal both for cam and crank. Timing is bang on and belt was replaced a few thousand miles ago. The van will run on easy start so no mechanical issues. Injectors don't seem to be firing. I don't own an oscilloscope as I would like to check cam and crank signal for collation but I would expect a Eml fault if it was out. I've spent a fair emount of time on this job and was hoping for some inspiration.

 

[mmi]

How it became a non-starter?

On crank it has good fuel pressure,

A number?

Injectors don't seem to be firing.

Does the ECU command them to fire?

Have you tried disconnecting camshaft position sensor (G40)?

Won’t start. No fault codes

Thank you very much Catfood12 I will certainly do that tomorrow and let you guys know how we get on I don't think you'll see anything, as the injection duration is at zero. When you said earlier it starts and runs on Easy Start, do you mean you have to keep feeding on Easy Start to keep it...

www.t6forum.com

 

[waynesturbo]

The van was driving and started to slow down with no throttle response, customer stopped and van still ticked over. She tried to go off again but it was very slow and finally cut out and never started again. AA came out and recorded a egr fault and towed her home. I know the family well and I was too busy to take a look so I suggested blanking the egr and trying it again. No joy, so it was towed to me. Fuel pressure is instantly up to 400bar then drops to 290-310 ish while cranking. I did try unplugging cam sensor but it still wouldn't start. Cranked several times allowing It to stop cranking on its own. After that a cam open circuit and signal fault was recorded. 2.5volts on all injectors and both pins while ignition on but no change on crank

 

[Dellmassive]

so rail pressures sound about right.

Intermittent starting issue

That's interesting... I was wrong, captured some logs on my way to the office this morning and the fuel pressure does drop when the stop start kicks in. Will post the log when I'm home this evening. Edit: Log now attached, 3 separate stop/start events captured.

www.t6forum.com

.

 

[Dellmassive]

will it fire with easy start?

fuel delivery problem then?

have you got access to VCDS or other?

to get live PID data on crank speed?

rpm signal?

injector fire and dwell time?

key and immobiliser all good?

 

[waynesturbo]

Yes it will run on easy start, so mechanical we know it can run. I checked the injector activation is .5 and duration around 1000. Going by a previous thread with similar issues as this one these values indicate the ecu is telling it to start, but nothing. I'll try to get the same recording as the other thread from my van for everyone's viewing. Yes I have vcds

 

[waynesturbo]

Won’t start. No fault codes

Nice, if i disconnect camshaft sensor, engine will start so i quess camshaft module needs to be replaced. I couldn do it correctly. I have hex+can cable andwhile trying to "Tick "Group UDS requests" - by 7" it says i need new interface. So i got only 1 time logging whivh didnt show anything...

www.t6forum.com

 

[waynesturbo]

The above thread has got good info