G40 Crank position sensor wiring 1.9tdi

[Demo8dan]

Hi all does anyone know where the wiring goes to for the crank sensor so I can test them out. I'm only getting voltage on 1 of the 3 wires and car is poor on starting. We have replaced the g40 already with new and stripped timing down and re done it which is spot on now but still poor on start. Fuel pump has also been charged.
Any ideas or tips would be greatly appreciated


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[hollows wife]

go to pins 42,58,57 of 60 pin connector on ecu . in that order 1,2,3 of crank sensor g28
the g40 is the cam sensor pins 27,28,12 of 60 pin connector in same order 1,2,3 - g40

have you tried another starter motor ?
see loads of vag cars with poor starting and lot of the time the starter is running slow even though it doesn't sound like it is .
engine has to get 720 rpm to start .so if its lower than this it would struggle .

also which fuel pump have you changed ? in tank or tandem ?

 

[Demo8dan]

Swapped starter m with another which I know works fine and it's the same. Pump in tank changed, fuel filter, housing and hoses with clips changed, battery also changed.

Vag com only shows error on g40 and won't clear. We've even got torsion value sat on 0.0 we'll bell out the cables you mentioned tomorrow thanks again pal all help is vital as we've got to a bit of a dead end with it atm and don't know what it is been working on it for ages.


German engineering

 

[hollows wife]

its the cam sensor you need then , yep these do cause poor start issues .

pin 1 usually 5v
pin 2 ground
pin 3 0-5v (whilst cranking should read between 0.8-1.5v

should be a plug near centre front of engine block close to rocker cover that links the wiring for the cam sensor into the main loom . should be good to get a pick up fom there

 

[Demo8dan]

Thanks we'll do some testing and report back


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[Demo8dan]

Pin 1 is neg
Pin 2 reads 1.45v
Pin 3 reads varies around 1.65v
These were read when the sensor is plugged in and engine running.


German engineering

 

[Demo8dan]

I think the PIN numbers are there other way round so 3 in neg


German engineering

 

[Demo8dan]

When the g40 plug is disconnected and ignition on I guess there should be 12v present on pin 1? Which there isn't in our case
Possible ecu is faulty?


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[hollows wife]

where did you connect to the sensor to get the readings ? at the ecu or at the connector where the sensor connects to the loom ?
could be a break in the wiring if you connected down stream from the ecu itself

 

[Demo8dan]

From the g40 connector in front of the head.


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[Demo8dan]

Wrong values on reading its actually
3 neg
2 4.99v
3 5v


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[hollows wife]

looks like the sensor is dead as it should have an output signal between 0.8-1.5v which will varies on engine revs .

 

[Demo8dan]

Sorry mate probably not laid info down correctly these values were read from the engine loom plug with ignition on g40 disconnected. I think I've sussed it i compared ohm values with another working g40 which were ok. The ring behind the cam sprocket is a bit battered and bent in places thing the previous owner has been tampering or their mechanic


German engineering