No fuel pressure

[Uberderv]

Hi all,

 MY 2001 hdi has decided to stop working today. It turns over fine but doesn't start, not even a blip like it is trying. It did struggle a bit yesterday morning too but started and ran fine all day.

 Soo... today after pushing it round the back of my house (off the main road) having somesort of asthma attack from blowing out my arse so much I have done the following.

 Removed in tank pump, stripped it and cleaned then tested with external power (seemed ok) removed FPR and cleaned the little mesh. Checked fuel is getting to the HP pump but the bugger still refuses to start.

 PP2000 is now only coming up with a known EGR fault. I checked cranking speed and its around 245rpm, cam and crank sync ok and ECU unlocked. Measured fuel pressure is a big fat zero. What could this mean?

 Really need to get this fixed asap so any suggestions will be most welcome.

[welshpug]

what pressure are you getting from the lift pump?

maybe a dead pressure sensor as i dont think they start firing the injectors unless they reach a certain rail pressure do they?

[Uberderv]

Sensor is reading zero all the time, not sure what the output pressure of the intank pump is but it appears to work every time the ignition comes on, when I had it in the bucket it seemed happy enough.

Something that did seem strange was the PP2000 could not connect to the BSI when I do the global test, I have no idea if this is important. Im still very new to PP2000, only re installed it today.

[welshpug]

if its a 306 theres no bsi.

[Uberderv]

if its a 306 theres no bsi.

That rules that out then And from what I've read it needs 120bar to start. I hope the HP pump ain't dead...

[mr_fish]

HP pump should see 300bar before it tries to fire iirc. Even a half knackard pump should see some pressure. From the rail sensor there is a wire that drops down towards the sump, then has another connector inline. Check that. Its right in the front where most of the elements hit it.

Definitely got fuel in it?

[Uberderv]

Yep got fuel, it spilt all over place when I removed LP pump lol. I'll check the HP sensor loom first then, summit ain't reet to display 0bar measured fuel pressure when cranking.

[Ruan]

Check loom - but would expect a fault to register from an open circuit.

When you put key on, EML should come on, LP pump should prime and then shut off after a few seconds - it's definitely priming the LP pump? Make sure it's actually running the LP pump to prime the system, if it's not, it could be the brown double injection relay, P0230 is the generic catchall code for "low fuel pressure in the HP circuit". That doesn't necessarily say the cause of the low fuel pressure fault of course, just that the fuel pressure didn't meet minimum to start.

Unfortunately these don't have detection for if the LP pump isn't running or is open circuit back to the double relay...

If you've had the FPR out the pump and run it manually and it's in the fully retracted position - this might be the reason for it making zero pressure, if the ECU is locked, from memory it doesn't even attempt to drive the FPR... I've found out to my own detriment myself that just because PP2k says the ECU is unlocked, it doesn't actually necessarily mean it is The fact it's not connecting to the BSI/CPH whatever you want to call it (yes we know it's technically not called the BSI, but PP2k calls it the BSI/CPH...) is slightly concerning - that might be more to do with it than you expect.

[Uberderv]

Well thanks for the help everyone, its now running. After checking all of the fuel related parts, stripping cleaning the LP pump, fitting a spare FPR, and eventually opening up the filter housing I 'think' the problem was the filter. Almost totally blocked.

With the housing off the car I cleaned the pressure relief valve, checked for metal bits (none present) in the base then cleaned it out with a solvent, the filter looked dirty so i decided to try and blow through it, it was almost impossible. So new filter on and it started up straight away.

 Thanks fook for that....

[Ruan]

Wow! I've never heard of that before - how the feck it wasn't cutting out under load long before then I'll never know!

What are you running it on? Pureed mud and shit?! Haha!

[mr_fish]

If the fuel filter was like that...perhaps a full service is in order?

[Uberderv]

Ha ha I was told it had been serviced before I bought it, maybe they didn't bother with the fuel filter one to keep in mind though...

[Poodle]

Thanks for posting the solution. Seen it a few times cutting out under load, never seen it get bad enough to prevent starting lmao. I'd be servicing it, or at least oil and filter and checking the rest.

[Uberderv]

It's funny, the actual filter was the last thing I checked. I tested fuel flow pre and post filter and admittedly post filter was less but I expected that due to the way the housing pressure relief works. When I took the filter out it was black, soaked it in solvent then tried back flushing it with lung power. After popping a vein and seeing all the shite being blown out it was clear it was blocked.

Lesson for me is basics first ie filters etc... Like Ruan says there is no LP pressure fault detection so things could of got expensive if I was the 'throw new parts at it type'

From research it was clear that the HDI needs 4 conditions met for it to start-

ECU unlocked.

Cam/crank synchronisation.

Correct RPM.

Fuel pressure.

If other factors effect any one of these it won't start ie low battery voltage, LP fuel system etc...