307 2.0 HDi RHR 136 wont run - no fuel pressure

[tmead]

I'm beginning to dislike this car very much...

It died when my wife was driving down the motorway yesterday. Apparently just lost power and she coasted to a stop on the shoulder. AA guy read the faults and was surprised about the 6 that were logged, but they are all ones I know about (EGR, turbo repeat, post heat relay, coolant bypass solenoid). There was a particulate filter blocked on there, but I've had that a couple of times recently, and at 190K its not unreasonable....
However, Mr AA man reported no fuel pressure as the reason for teh failure. I've checked now with all faults cleared, and PP also reports zero measured fuel pressure when cranking. Crank speed is over 200 rpm. Seems odd that the pressure doesnt rise from zero at all.

crank and camshaft synch is OK, and it will cough on easystart, so I'm assuming that the cambelt is OK - anybdy think I need to check ?
Revs are shown in PP, so crank sensor is OK
diesel filter was replaced around 3-4K ago, so unlikley to be that
fuel tank was recently filled, but receipt clearly shows diesel

I've looked at the HP pump as much as is practical, and it does look slighty damp around the lower half - not wet and there is no evidence of diesel below it. I don't know how to check the HP pump, and have no measureing kit
The connector to the fuel rail pressure sensor behind the air doseur is tight, wires all look intact and the contacts are clean

All suggestions welcome.

[RichardW]

Assuming cam crank synch goes from no to yes as you start cranking, then the belt is OK. On these the pump is driven off the other end of the cam IIRC? If you open the drain on the filter and pump the primer does anything come out? After that, you're down to replacing the pressure sensor, and if that doesn't work, then replacing the pump...

[tmead]

Yep, the synch sits at no when ign on and changes to yes when cranking. I assumed that meant belt was OK. It was changed around 20K ago for a complete gates kit, so should be fine.

On the RHR 2.0 16V the pump is indeed driven off the gearbox end of the rear camshaft. (vac pump on front one)

I'll check on the filter drain, I can see a couple fo small bubbles moving in the pipe when I squeeze the bulb. There's definitely deisel in there.

Is the pressure sensor a common failure ? Its a bit of a sod to get to, but not too bad. I guess as the cheaper item this is the one to go for first !

I had wondered about the pump, and may try to source a secondhand pump. At 190K its not worth a new one.

[tmead]

Just a thought, how would the sensor fail to indicate zero pressure ? I haven't managed to find a specification for it, but if sort of expected that zero would be a small voltage, full scale pressure something like 4.5, as that then means zero volts or 5 volts would be an error ?

[wheeler]

What reading do you get if you unplug the sensor? Normally goes to 450 ish bar.
If i am investigating a low/no fuel pressure fault on an HDi i would also do an injector leak back check as a faulty injector can stop the pressure buildup in the rail too.

[Gibbo2286]

Just a thought, silly probably but the C5 I have with the same engine had a pin hole in the rubber priming bulb where it had rubbed on a bracket, that was enough to stop the fuel getting to the place it ought to be.

[RichardW]

I had another thought that you should check the inertia cut out, if it's got one - sometimes they just spontaneously trigger!!

[wheeler]

No inertia switch on this model.

[tmead]

Thanks for the suggestions ! I've squeezed the bulb and no fuel squirts out anywhere, so I dont think there's a hole ?

I'll try unplugging the sensor tomorrow. See what that shows.

I had thought about a duff injector - but I'd be surprised if that meant zero rail pressure. I would have expected some ? I'll grab some tube and some jamjars and try to sort a leakback check of sorts. To get zero pressure in the rail it would need to be pretty noticable !

[tmead]

Thinking on a bit - not sure I can do a leak off check, as the engine wont run. It would have to be a huge leak off to show in 10 seconds on the starter ?

[Gibbo2286]

Disconnect the pipe between the primer bulb and the filter to see if the fuel is getting that far to eliminate faults, air leaks, blockages, etc., in the line from tank to pump.

[tmead]

Not good news.

Disconnecting the sensor resulted in a pressure of around 390 bar reading when cranking. Reconnecting brought a steady zero.

Primer pumps fuel through return line into a jamjar, cranking does not. Leads me to believe it's the hp pump. I popped that off, and the bad news showed. Theres supposed to be a yoke on the end of the camshaft with a joint inside around the pump shaft. That yoke is broken off. I'll need to get the rocker cover off to look for all the bits.

How much of a ball ache is it to change the exhaust camshaft ? Is it worth it ? Any ideas where to get one ? So many questions.

Broken bits

End of camshaft

[tmead]

Pump rotates readily by hand, so isn't seized. No real reason for this yoke to snap off.

[RichardW]

Bugger....! Book time is 7 hours, and involves removing the injectors, so not going to be a walk in the park! Be just as easy to find another engine....

[tmead]

Just thinking. I guess if I'm changing the camshaft I also should change the chain and seal ? Anything else ?

Cambelt was changed around 30k ago, so no plans to replace it.

I'd like to take a look inside the rocker cover and make sure the cam is ok, but don't have time before I need to order parts.