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On my way to number one childs wedding last Monday and the pug conks right on the magic roundabout in Swindon. Managed to coast off the busy bit and onto a verge (phew!!), abandoned her and hot footed it to the registry office and asked big bruv to attend the recovery.

Apparently the recovery guy after towing it to my house diagnosed 'fuel filter' as the problem. It's had to wait til today for me to have a look. Took the old filter out, wasn't horrendously filthy, and slotting a new one in made no difference. Cleaned out the housing, examined what debris was there expecting to maybe find bits of tank motor debris (lift pump still operates normally judging by the sound behind me when I turn the ignition on) but all fairly clean, wee tiny bits of grit were all I could find. There are two solenoids in the engine fusebox which buzzed furiously for about 20 seconds at one point.

My thoughts are:
1. The tank pump is fine.
2. It's possibly just dirt (how to clean??)
3. The high pressure pump is expensive and a bar steward to swap out - and thus shall be assumed working until all other avenues are exhausted
4. The buzzing solenoids (loom corrosion??) if I read the wiring diagram correctly goes to sensors on the MAF, turbo, somewhere else and the high pressure fuel pump (aha!), so may or may not be a factor
5. It's cold out.
6. I write posts that are far too long to be of interest
7. Sorry about point 6
8. Any ideas? What to test next? Just how DO you check fuel pressure on a diesel? Will PP2000 be of any use? (I got one but the cars OBD socket +12v pin is dead grrrrrrrr).
9. All help hints, suggested modus operandi, or, well, anything really very gratefully received.

Buzzing solenoids are not unusual.
To be certain the lift pump is OK observe the fuel filter housing as the ignition is switched on - if all is well the housing will physically swell a tiny bit - the lift pump delivers about 4-5 bar.
Assuming that's OK, check the fuel pressure regulator - it apparently has a tiny filter as well. (don't know the detail but search 'fuel pressure regulator').
Is it turning over fast enough? (ecu has to 'see' about 60 RPM before it will fire the injectors).

Get your PP2000 working if possible. The lack of +12 on the diagnostic port is probably just a fuse, which one varies according to the age of your car. If all else fails, remove / test every 10A fuse in the engine compartment fusebox.

Keep us posted & we'll try to help.

Congratulations to number one child & spouse.

Yours is the exec, so I think the 2 buzzing things in the engine fuse box are the heated seats relay and blower relay...
The fuel pressure regulator is on the rear of the pump, held on with 2 torx bolts. There are 2 o rings and a filter(sometimes!) on the end.
Definitely get PP2000 up and running, you can check the fuel pressure from this, as well as injector values and cam/crank sensor synchronisation.
Check the headlight washer fuse - I think this is also the fuse for the OBD port.

The fuel pressure regulator is on the back of the HP pump but not difficult to remove. there are usually a few secondhand ones available on ebay for not to much money.https://www.ebay.co.uk/sch/i.html?_from ... i&_sacat=0

Peter

It goes without saying to be VERY CAUTIOUS 'opening' a high pressure fuel system for inspection, make sure (by whatever means applies) that the system is not pressurised before you do any kind of spannering on it for yours and anyone helping's safety.

Agreed. The HP pump will deliver 250-300 bar while cranking or idling & 1350 bar at full chat, so needs to be treated with caution.
Pressure dissipates as soon as the engine stops so less of an issue if it's not actually running.

Hi everyone! Right then its Sunday, I have been buggering about with it all morning - mostly trying to fix the OBD socket - what a pain in the bum! I left the laptop on while sorting that and by the time I ran PP2000 the battery was nearly drained but I did manage to get a fault saying crank sensor no signal received (or was it cam?? Shoulda wrote it down d'oh!!!) I have chores to run now so once laptop is charged I should be able to leisurely go through all the options. Oh one other thing it said was fuel pressure 0bar preferred value 2bar but I guess thats because the engine wasn't running. I am a total novice with PP2000 so apologies if this all sounds like deranged nonsense.
Laters chaps! And thanks for the warning on the high pressure meddling. The filter housing securing ring is murder tight even with the engine off as it is so I can imagine 300 bar will put holes in me and will spoil my day somewhat.

More info. Been out in the dark and the cold with a freshly charged laptop OBD port permanent live sorted with a bodge wire off the fuse box. The correct wording from pp2000 is:

camshaft/crank sensor synchronisation=no.

Apart from that, not much of a clue - would I be right in saying that unless the engine is running you cant actually check the fuel pressure?. If so, thats me buggered lol

Too dark to check the sensor wiring now. When that has been eliminated I think I will try the pressure regulator after that and go from there. Cheers peeps. Watch this space --->□

Without cam/crank synchronisation your car won't start - so best check these connections first, replacement parts are not too expensive and easy to replace.
Maybe a failing crank or cam sensor is why your car broke down in the first place, as soon as the synchronisation is out then it's a no go.
Get this sorted and your car will probably start.

Just a word of caution - not 100% certain, but no synchronisation is I think normal if it's not running, (makes sense I think).
I suspect sync is what it's looking for while cranking, (which is why they don't fire instantly).
Possibly sync will change to YES just as it fires, but you probably couldn't spot it due to display latency, (just my theory).
If I get a chance later in the week, I'll try stopping mine from starting by unplugging the injectors and see if sync changes as described above.

Another Sunday, two weeks without a laptop and hence pp2k, finally got it fixed. Dead battery by now (of course!) So... after charging my poor old battery for the best part of the day the time at last comes to do parameter test... only to find that bodging a twelve volt live via the fuse box as the supply is momentarily interrupted during cranking (says to self: "No sh*t Sherlock!"). This causes pp2k to say "comms interrupted" and boots out of parameter mode. So its a further overnight charge for the battery and an extra long bodge wire direct to the positive terminal. Thank god for number one child's learner motor... look out for more gun and fames in the next exciting installment... whenever that may be.

Finally I have a +12v direct live to the OBD, a working laptop and a charged battery. I think I may have traced it.

In parameters 1 engine RPM stays firmly at zero during cranking. Would you fine gentlemen have cause to disagree with my conclusion that I may indeed have a dead crank sensor as suggested?

Finally I have a +12v direct live to the OBD, a working laptop and a charged battery. I think I may have traced it.

In parameters 1 engine RPM stays firmly at zero during cranking. Would you fine gentlemen have cause to disagree with my conclusion that I may indeed have a dead crank sensor as has been suggested?

I suspect you're right. It's a long time since I've watched that page while turning it over, but I'm fairly sure you will see an RPM reading before it fires.
I am sure you can see the fuel pressure go up to 200 - 300 bar within a couple of seconds so I'd be amazed if you didn't see something other than zero for RPM.

(If anyone can confirm or deny please do so).

My memory of pug things is bad, but I'm almost certain you should read engine RPMs while cranking. Crank sensor fault will absolutely kill a car dead cos it doesn't know when or on which cylinder to fire up the injectors (and coils on petrols)...

Try the wiring before faffing about replacing the sensor. Unplug the sensor, give the connectors a blow, or a shot of contact cleaner/isopropyl alcohol if you've got some, then re-plug it. Check as much wiring as you can see for signs of damage. Although, PP2000 should report an open circuit or short if that's the case but it's always worth a try.