HELP NEEDED!! Starting issue, stage 2 mk1 Leon FR

[mickyushleonfr]

Hi

I have a mk1 Leon FR, 1.9 tdi pd150 currently running stage 2 mods.

I have a starting issue which will not got away!
It is turning over for ages and eventually tries to cough it's way into life.
Sometimes it doesn't want to start, but eventually it always will.
Eml came on with a crank sensor code and the glow plug light is flashing.

So far I've had replace
-crank sensor
-cam sensor
-glowplug relay
-brake switch
-temp sensor
-glowplugs

The car has recently been serviced but the problem occurred before that anyways!

Sometimes the rev counter will bounce when trying to start aswell.

Any ideas?
Help much appreciated

Thanks
Mick

 

[Thai-wronghorse]

Any fault codes?

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[mickyushleonfr]

Only code that came was a crank sensor one, can't remember the exact code number

 

[mty12345]

The fact that the rpm bounces like you describe, would definitely make me think the crank sensor too. Maybe the wiring to it is faulty or the replacement sensor is also faulty?

 

[Thai-wronghorse]

Was it a genuine sensor?

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[mickyushleonfr]

Yeah genuine sensor and I have replaced it twice in case it was faulty, still no different, I have read somewhere maybe a pickup pipe is full of gunk in the sump? Causing the crank sensor to get no signal?

Have also been told that is not the case as there would be other symptoms

 

[mty12345]

Yeah genuine sensor and I have replaced it twice in case it was faulty, still no different, I have read somewhere maybe a pickup pipe is full of gunk in the sump? Causing the crank sensor to get no signal?

Have also been told that is not the case as there would be other symptoms

No mate, whoever told you that is talking crap. The crank sensor is an electrical sensor on the flywheel, the pick up pipe sucks oil into the engine from the sump. The 2 things are completely unrelated.

If you're still getting a code for the crank sensor and the "bouncy" rev counter too, then it must be the wiring to the sensor imo. Unplug it and check there's no corrosion or build up of crap on the pins.

If you have vcds or the torque app, see what the revs are saying as the engine trys to start. If you're getting crazy high numbers then that would confirm a crank sensor problem.

Otherwise get a auto electrician or seat dealer to check the wiring between the sensor and the ECU.

 

[mickyushleonfr]

Thanks will get that checked out.

I'm not the very clued up with the mechanical side of things, little jobs yes, confusing **** like this no lol
To me it sounds like it's a fuel related problem, as it tries to start a few times before it actually kicks into life.

But like I say I'm not that clued up.

 

[mty12345]

No worries. It could be fuel related, but for the reasons above i'd still be looking at the crank sensor.

The crank sensor is the one sensor on a modern engine that will cause the car not to start if it fails. Most engines will make an educated guess if any other sensor fails, but the crank sensor has to be giving the correct signal as the fuel injectors (and the ignition timing on a petrol) use the crank info to determine when to fire.

 

[mickyushleonfr]

Yeah I'm with you, cheers

My mate going to have a look Friday so will update if any joy.

 

[mty12345]

That's cool buddy and yeah let me know how you get on.

 

[mickyushleonfr]

Had a new starter motor fitted and that has solved the problem!