Pump learn help

[loot]

I don't trust eBay

[Rumpleforeskin]

Ok guys Ive just fitted a Ford fuel filter (£36)!!!!! And its made no difference whatsoever! I was thinking of taking the tank off and cleaning it but I dont think it could be that, fitted new filter full of clean diesel and the engine was surging and cutting out after only a few seconds. Surely it would have plenty of diesel in the filter to run well for a little while! Im back to square one again, open to any suggestions, got quoted £180 for an scv at Fords today, Im very reluctant to pay that unless Im sure thats what the fault is.

[mjsroofing]

Ok guys Ive just fitted a Ford fuel filter (£36)!!!!! And its made no difference whatsoever! I was thinking of taking the tank off and cleaning it but I dont think it could be that, fitted new filter full of clean diesel and the engine was surging and cutting out after only a few seconds. Surely it would have plenty of diesel in the filter to run well for a little while! Im back to square one again, open to any suggestions, got quoted £180 for an scv at Fords today, Im very reluctant to pay that unless Im sure thats what the fault is.

When changing filter, fill to the brim, start engine and hold revs on about 2k for a few seconds to pull all the air through, if it cuts out, refill filter and repeat procedure.

[Rumpleforeskin]

Its pretty much to the point now where it just cuts out as soon as you dip the clutch, approaching roundabouts or junctions, slowing for traffic, if you dip the clutch it stops! It does restart straight away though strangely??

[Rumpleforeskin]

I did fill the filter Mark, just been for a drive around in it, still just cuts out all the time its a nightmare driving to work

[loot]

Those prices are a bit steep
You'll need to get someone to have a look at live data and see if they can see the problem, fuel rail supply and demand etc.

Can you get someone to turn the ignition on and you feel the scv and see if it clicks/buzzes.

[Rumpleforeskin]

Yeah can do Loot, would the scv effect performance throughout the rev range or just a idle?? There is a slight hesitation if pulling from really low revs but otherwise the van runs great, as long as you can keep rolling theres no problem, its stopping thats the problem as it just wont idle and stalls

[loot]

Yes the scv is in charge of maintaining fuel pressure.

The fuel pump just pumps high pressure to the rail, the fuel rail pressure sensor sees the pressure and at max it tells the pcm which controls the scv it opens and closes and that (in a nutshell acts like a tap) and restricts the amount of fuel that goes to the rail, what happens is after a few years, crap and wear get to the scv and (for all intents and purpose) the scv can't keep the pressure under 1600 bar which causes the prv to pop which saves the rail and injectors.

Pump and pilot learn initially synchronises all the fuel components optimally but in the end the valves become US.

Although at worst it usually hunts and occasionally cuts out at junctions, if yours is dying quite rapidly then there's a leak somewhere

Ideally someone who has done lots of these will be able to narrow it down quickly and economically.

I would want to look at the valves and if look at the fuel filter head as they are common fail points, and the injectors leak off test too because if 1 is shagged it could be allowing fuel pressure drop.

But without looking at it all and knowing, it could be a spending spree

Injector leak off-free.
O rings check/ seal-free.

[knobby1]

Yeah can do Loot, would the scv effect performance throughout the rev range or just a idle?? There is a slight hesitation if pulling from really low revs but otherwise the van runs great, as long as you can keep rolling theres no problem, its stopping thats the problem as it just wont idle and stalls

Yep, do as Loot says, the SCV controls all fuel pressure, from idle through to full noise...The SCV is just a "variable" spring loaded solenoid valve, if the little piston sticks at all it will cause grief, old age and years of crud going though it will eventually wear it out....replace it and the PRV, then do a full set of learns (with PCM update if required). With all things being equal and the injectors are ok, you should be fine.

The learns will fail if the injectors leak-off checks aren't up to snuff anyway.

Lord Knobrot

[bambi mk 1]

Its pretty much to the point now where it just cuts out as soon as you dip the clutch, approaching roundabouts or junctions, slowing for traffic, if you dip the clutch it stops! It does restart straight away though strangely??

If you sit in the van and start it will it stay running and cut out when you dip the clutch

[mjsroofing]

Would a visual of the scv show faults.

What do I need to look for on live data, I'll see if I can organise a time to meet up with Lee again then,

Pilot learn passed twice with no problem, pump learn took a few times before it worked.

[loot]

Usually the other way around Lol.

[knobby1]

Would a visual of the scv show faults.

Yeah...but you need to remove the tiny circlip and dismantle it to check the little sliding piston valve & spring...bad score marks in the bore and on the piston will usually spell the end of it. The more the piston valve sticks in the bore, the more the engine will "hunt" on idle. I think the correct term for it is "hysteresis".

Lord Knobrot

[mjsroofing]

Thank you knobby knobrot, sorry I mean Lord knobrot.

Another free option for Lee to try.

[Rumpleforeskin]

Hi guys, just stripped the scv, it didnt look to bad with just very light marks on the piston. When I slid it in and out of the bore it felt smooth with no signs of sticking, while I was there I gave the connections a good bast with contacy cleaner. Ive just refitted it and the van is running perfect!! Gone for my usual blast around local that normally throws up the bad running again and its still running perfect, tickover bang on, no stalling. I'm going to drive it to work tomorrow and will let you know how it goes thanks again all for your help in this, fingers crossed its sorted. And at least I am confident now that it is the scv, how unlucky to have a second pump fitted that is just as bad as the first one!!