General: Won't start - Guess the fault code competition

[AL5XC90]

I reckon I'm barking up the wrong tree here. Fault codes were P0094 Fuel leak (small) and P0087 pressure too low.

I have replaced the fuel filter. Having cleared the codes, I get no further codes thrown.

ODB reader shows fuel rail pressure oscillating between 0 and 210 KPa with ignition at position II.

No change in FRP KPa reading on cranking (oscillates between 0 & 210 KPa).

This feels like its something really simple. Its driving me insane.

[cheshired5]

With such a poor cranking figure, either.....

the pressure isn't being generated by a failing HP pump (less likely but not out of the question)

the pressure regulator is faulty or the control of it

rail pressure sensor is incorrectly reporting otherwise good figures

Check and double check all connections, particularly the pressure regulator plug which can be easily disturbed.

[Acer]

Originally Posted by AL5XC90

I reckon I'm barking up the wrong tree here. Fault codes were P0094 Fuel leak (small) and P0087 pressure too low.

I have replaced the fuel filter. Having cleared the codes, I get no further codes thrown.

ODB reader shows fuel rail pressure oscillating between 0 and 210 KPa with ignition at position II.

No change in FRP KPa reading on cranking (oscillates between 0 & 210 KPa).

This feels like its something really simple. Its driving me insane.

Could be as I noticed you have a 54 plate and I think the CEM issue started with 05.

[Horton]

Originally Posted by Acer

A repair is not always possible. Depends on what is damaged. Personally I would want brand new, as the CEM is critical and once water has got inside then who knows what else will go wrong.

Bear in mind only Volvo can code a new CEM and you can't just grab one from a breaker.

A good Indy with proper VIDA CAN programme a CEM - I can...

Couple of thoughts reading between the lines, and I know some of these have been mentioned before......You say you changed the fuel filter, but how much have you cranked it over, or have you left the ignition on to allow the fuel to make its way up to the HP pump? It takes quite a bit to get a d5 going after a filter change?

Have you cracked off an injector pipe to see if you have fuel pressure?

Check the wiring to the fuel pressure sensor on the common rail?

Have you undone a fuel feed pipe to see if you have pressure from the pump? It doesn't sound like a CEM to me, I think you have a faulty fuel pump. In your first post you say it started again, and then died.... And then wouldn't restart? Very similar to running out of fuel....? My money is on the tank pump. A CEM usually manifests itself as an intermittant cutting out, rarely a total non start?

[AL5XC90]

Ah haaaa.

Its the high presure pump I think.

Ignition set to II there is a low buzzing in engine bay in HP pump area.
If i disconnect the fuel rail pressure sensor the buzzing increases to sound like an angry metallic wasp in a jam jar. Constant, never ceases.
If i plug sensor back in it drops to low buzz.


I dont think its the regulator, which looks much easier to swap!

[Horton]

Never had an HP pump fail..... But there's a first time for everything!

[luggsey]

Originally Posted by AL5XC90

Ah haaaa.

Its the high presure pump I think.

Ignition set to II there is a low buzzing in engine bay in HP pump area.
If i disconnect the fuel rail pressure sensor the buzzing increases to sound like an angry metallic wasp in a jam jar. Constant, never ceases.
If i plug sensor back in it drops to low buzz.


I dont think its the regulator, which looks much easier to swap!

Can they sound like that if they are dry?
Just a thought.

[AL5XC90]

Mmm. Hadnt thought about dry running.

I guess i can crack an inlet hose and check for flow on cranking to verify fuel reaching pump. Will try that in daylight.

[luggsey]

Originally Posted by AL5XC90

Mmm. Hadnt thought about dry running.

I guess i can crack an inlet hose and check for flow on cranking to verify fuel reaching pump. Will try that in daylight.

After changing the fuel filter I cycle the ignition four or five times until the lines are refilled and air purged, you can hear the fuel pump and the gurgling fuel if it's working?

[AL5XC90]

Thanks all for your comments/suggestions so far. Really appreciated.
My garage is likely to be open tomorrow but I really fell I should be able to diagnose this myself, at least to a general area even if I can't fix it myself. I'm gonna a feel a right plank when I tell them I've stared at it for 5 days or so and then they push a button and the car roars into life

Couple of thoughts reading between the lines, and I know some of these have been mentioned before......You say you changed the fuel filter, but how much have you cranked it over, or have you left the ignition on to allow the fuel to make its way up to the HP pump? It takes quite a bit to get a d5 going after a filter change?

I've tried ignition on/off for 30s for 10 mins to prime. I've tried cranking for 20-30 secs several times in a row. No change (apart from flat batteries)
No Gurgling sounds from engine bay. Only sound from rear of car and the buzzing in engine bay in my latest post.


Have you cracked off an injector pipe to see if you have fuel pressure?

Yes - no fuel came out, even when cranking

Check the wiring to the fuel pressure sensor on the common rail?

No obvious damage

Have you undone a fuel feed pipe to see if you have pressure from the pump?

This is my next daylight test.

It doesn't sound like a CEM to me, I think you have a faulty fuel pump. In your first post you say it started again, and then died.... And then wouldn't restart? Very similar to running out of fuel....?

Defo seems to be no fuel reaching the injectors.

My money is on the tank pump.
When I turn ignition to II I can hear something in the rear of car, it increases in pitch after about 30 seconds, then stops 10-15 seconds later.