C5 1.6 HDI won't start

[NutsAndBolts]

I have a Citroen C5 1.6 HDI which won't start following a forced regeneration that I was running using a Lexia 3. The Lexia reported: regeneration complete with errors. The car now turns over but doesn't fire.

Prior to it not starting, I have had a long standing problem where the car would not rev up beyond about 3700 rpm. I was thinking the regeneration might fix this but it broke the car instead. The regeneration tries to hold the car at 4000 rpm, and so engine was not happy during the procedure and just sounded like it was red lining the whole time.

So now the car won't start and on checking the fault codes I thought it was the crankshaft position sensor because of this fault given by the Engine ECU: P0339 Engine speed signal Signal temporarily incorrect or missing (Temporary). However, I checked the wiring which seemed OK: no shorts to earth or positive, a good connection between ECU socket and sensor socket terminals, also I can detect a voltage to the socket when the ignition is on. I then replaced the sensor and this did not help. I have replaced the crankshaft pulley thinking perhaps the magnets were damaged but this has not helped either.

Does anyone know if it normal to get P0339 when cranking the engine but before it fires? The code is "Temporary" so perhaps this is a red herring? I see that the fuel pressure is low while cranking and keep thinking that it is just the High pressure pump that has gone. But is this possible with all these other error codes?

There are lots of errors relating to communicating with the engine ECU. Does the engine ECU communicate with the other ECUs (ABS etc) before the engine starts or is it normal to get these fault codes before the car fires and perhaps they clear when it starts running?

I have had the ECU replaced recently by a garage for the limited rpm issue, which it didn't resolve, and suspect the ECU is OK unless maybe it has got into a funny state as part of the regeneration cycle.

Perhaps the fault F4C4 engine oil pressure - Not characterised could be an issue. It does have oil in it but maybe there is a sensor problem or maybe its just that the ECU is not sending the information to the BSI?

Thanks in advance for your expert advise.

Lexia 3 output below:
BSI
fault codes present
engine oil pressure - Not characterised
2IZ - F4C4
EDC16C34_DV6
fault codes present
Engine speed signal Signal temporarily incorrect or missing Temporary
HIZ - P0339
ESP_MK60 (ABS)
fault codes present
Engine ECU operation
1IZ - U1308
No communication with engine ECU no signal
0WV - U1108
No communication with engine ECU Data invalid
0WX - U1208
SUSPENSION_ECOTECH
fault codes present
Permanent fault No communication with the steering wheel angle sensor incorrect value received
0JX
Permanent fault Data invalid engine ECU incorrect value received
1AX
Temporary fault No communication with the steering wheel angle sensor no signal
HJV
Temporary fault No communication with engine ECU no signal
HNV
Temporary fault No communication with the ABS ECU no signal
I2V

[Lighty]

Doesn't sound to good, if the engine failed after revving at this speed.
1st you need to check for cam & crankshaft sync, whilst cranking. This will show that the belt & chain are correct.
Assuming this is ok, I would try & start it on a supplementary supply, such as easy start etc. this will show if the engine is in one piece, and mechanically runs.
I had a fault similar to this yesterday, it was the rail pressure switch giving false readings at high revs, the engine would cut & not restart easily, but would fire straight away if you disconnected the battery for a second.
New switch cured the issue, the guy had previously replaced everything

[CGATCX25GTITURBO]

New switch cured the issue, the guy had previously replaced everything

Everything but the switch

[NutsAndBolts]

Thanks for your help Lighty.
Just wanted to give and update on this in case it helps someone else in the future.
I took it to a garage who had it for over 2 months and the following work was carried out:
ECU tested - no problems.
Injectors tested - no problems.
High pressure fuel pump tested - no problems but reconditioned anyway.
I ended up selling the car and was informed within a week that it is now in full working order!
The fix to get it started was just to replace the crankshaft sensor again. So I guess that Euro carports sold me a faulty or incompatible sensor. Or perhaps I broke the sensor by testing it with a multimeter.
The problem with it not getting beyond 3500 rpm (limit revs) was apparently caused by a leak in the vacuum pipe which controls the turbo.
Hope this helps.