C5 diesel intermittent engine fault.

[Trialen]

Hello all,

I am hoping someone may be able to advise me about an intermittent fault on my 2006 C5 diesel. The symptoms are:

1. Engine occasionally cutting out while driving.
2. Engine occasionally failing to start.

The faults occur just often enough to destroy confidence in the car.

I have had the fault codes read, with the following results from the log:

53 times - code 7151 Engine speed info.
20 times - code 0337 Engine speed signal SC between two wires or OC.

Any help would be greatly appreciated.

[GiveMeABreak]

For P0337, you probably need a new engine speed sensor as this recorded as: Engine speed signal: Signal not coherent. There is an incoherent number of teeth on the target of the engine speed sensor: No long tooth on more than 6 CAM heads (No. of heads arising from the camshaft sensor signal to confirm the synchronisation with the crankshaft sensor (TDC).

This will result in cutting of the injection if there is a resynchronisation failure. Suspect areas are: Engine speed sensor, Engine speed sensor target, Electrical harness or Connector.

Code 7151 is not recognised - so not a PSA code as there is a letter missing at the beginning.

[wheeler]

This is a known fault on this engine, you need to replace the crank sensor and replace the connector with a modified one that has better connections.
With the engine running you can usually make the fault happen by wiggling the plug on the sensor. Be very careful doing this as its right next to the moving crank pulley & belt.

[GiveMeABreak]

This is a different name for the same sensor to avoid confusion.

[Trialen]

This is a known fault on this engine, you need to replace the crank sensor and replace the connector with a modified one that has better connections.

Can you give any more details about the modified connector? Thanks.

[Trialen]

Code 7151 is not recognised - so not a PSA code as there is a letter missing at the beginning.

My mistake, I just wrote down the numbers. I think it was P7151. Thanks.

[GiveMeABreak]

No, codes listed for P7151, P1571, P1751 for this engine, but I'd focus on the sensor now and or check the connector as Wheeler mentions.

[wheeler]

This is a known fault on this engine, you need to replace the crank sensor and replace the connector with a modified one that has better connections.

Can you give any more details about the modified connector? Thanks.

I’ll try & dig out a part number for you tomorrow. You cut the old plug off (noting the wire positions first) and if I remember right the new plug is pre wired with a few inches of wiring. Again if I remember right the terminals are gold plated the same as Renault done with their crank sensor connections.

[wheeler]

Also do you have the VIN or Reg of the car available? I need some further details of the car.

[Trialen]

Also do you have the VIN or Reg of the car available? I need some further details of the car.

VF7**************[VIN obfuscated, can be read by forum staff]

[wheeler]

OK the fault in question apparently on affects vehicles with an RP number range between 10736-10816.
Yours is well before this so may just be a failing sensor. on the affected sensors the pins are known to oxidise & cause a poor connection.
Try & see if you can replicate the fault like i said by carefully wiggling the sensor connector.
In the meantime i'm still trying to find the part no of the modified plug incase it is needed.

[Trialen]

OK the fault in question apparently on affects vehicles with an RP number range between 10736-10816.
Yours is well before this so may just be a failing sensor. on the affected sensors the pins are known to oxidise & cause a poor connection.
Try & see if you can replicate the fault like i said by carefully wiggling the sensor connector.
In the meantime i'm still trying to find the part no of the modified plug in case it is needed.

Unfortunately, with my engine, the sensor is behind the wheel arch, and you have to remove the wheel to get to it, so it's a bit hard to test. Thanks.