seat exeo crank position sensor

[Bobtail4x4]

ok people, my exeo has a problem, the crank sensor has been playing up, wont start when hot etc,
obd 11 says crank position sensor intermittant fault, as did the garage box of tricks,
struggling with mobility after an op, took it to a audi specialist in York,
changed the sensor and its no better,
now they say the gearbox had to come off as the flywheel sender part needs looking at,
while its off I may as well have a new clutch, do I ned a one piece flywheel as well?
or is it just something on the flywheel?

 

[Chippie]

I think there are less expensive options to consider first before removing a cog box…like scoping the output from the sensor, checking the wiring, checking the signal is reaching the ecu…remove the sensor and do a boroscope thru the aperture…

just saying…
A lot easier and cheaper than reaching for the spanner’s and hammers…

 

[Bobtail4x4]

they say they checked the wires and the ecu is ok

 

[Moose McAlpine]

What engine is it, and what is the actual fault definition?

 

[Fazerruss]

Have a look at a manual and parts list first. I would have thought the crank sensor will just be a hall effect sensor. If so the the flywheel doesn't have a sender unit . It would just have a series of holes in the flywheel.
Holes shouldn't go faulty!
I can understand it if was abs issues as the reluctor rings are exposed the the elements and go rusty. Even then it's usually the sensor or wires

 

[m_c]

As it's heat related, it's unlikely to be a flywheel issue.

If I was to take a guess, it's possibly a camshaft sensor.
Depending on the vehicle, crank sensor faults can be a fairly generic fault triggered by various things, but a quick data list check should tell if the crank sensor itself is actually working. Then you can check the Cam shaft sensor is syncing correctly, before doing further checks.

 

[sako243]

They may not have installed the new CPS correctly. They're pretty sensitive to having the correct spacing from the flywheel.

Scoping the output from the CPS would be my first port of call.

 

[Chippie]

They may not have installed the new CPS correctly. They're pretty sensitive to having the correct spacing from the flywheel.

Scoping the output from the CPS would be my first port of call.

The assumption is that it’s a genuine VAG cps and not a pattern part….

 

[sako243]

The assumption is that it’s a genuine VAG cps and not a pattern part….

That's fine but, for example, there are multiple variants of the one for the Rover V8 EFI engines depending on whether it was manual or auto. Both fit but they have subtly different standoffs and that makes the difference in working or not.

 

[Chippie]

My comment above was based on experience of our local VAG techies who I use from time to time….My sons Tiguan need a new pressure sensor for the ( Cat or Dpf, can’t remember which now…) they say use gen parts as the patterns even though maybe branded (Bosch…) may still not correct a fault….

 

[Bobtail4x4]

What engine is it, and what is the actual fault definition?

its the 2 litre 143bhp diesel lump

 

[m_c]

I'd probably be checking the physical timing before removing a gearbox on a 2.0l