Technical 1.3 Diesel - P0089 and the fuel filter of doom...

[Bantamsteve]

Hi matt ,hope your getting better,so hope this helps a bit, i must point out that im a joiner not a mechanic ,but im very enthusiastic ,the code is slways p0089,the 3 bolts on my FPR are indeedt25,there about 15mm long on mine there was a plastic looking gasket i reused it as it looked fine.The t25 long reach bits need to be not that long as by the time you but a socket handle on the end they foul against the battery , i had to undo the harness for the battery wedge the battery up to get the top screw out in fact i used a screwdriver,.btw i can remove the eml with about 3 cycles of the igition key on and off .The fpr is just below the diesel pump to the front right of engine it took about 40 mins to change .good luck and gws ,regards steve

 

[Matt Quinn]

Hi matt ,hope your getting better,so hope this helps a bit, i must point out that im a joiner not a mechanic ,but im very enthusiastic ,the code is slways p0089,the 3 bolts on my FPR are indeedt25,there about 15mm long on mine there was a plastic looking gasket i reused it as it looked fine.The t25 long reach bits need to be not that long as by the time you but a socket handle on the end they foul against the battery , i had to undo the harness for the battery wedge the battery up to get the top screw out in fact i used a screwdriver,.btw i can remove the eml with about 3 cycles of the igition key on and off .The fpr is just below the diesel pump to the front right of engine it took about 40 mins to change .good luck and gws ,regards steve

Thanks Steve... Aye well; I'm a cameraman... been mucking about with cars since I was a kid; and part of my training does touch on electro-mechanical systems; but I'm certainly no mechanic either. - I think the main thing that's frustrating me is the lack of information out there. Cars (like all machines) develop common/stock faults; as the part is readily available, I'm inclined to think this sort of thing isn't uncommon. - Yet; you're the first to confirm even the size of the bolts and that there is actually a gasket!

Interesting that the EML clears on its own; it's done that for me at least once... Logically; this all seems to point to the low pressure/fuel supply side. - I'd be interested to hear if clearing those odd bits of crud out the lift pump, cures your problem.

 

[Bantamsteve]

Hi matt you will probably hear a very loud cheer if/when i sort this out ,bearing in mind it was at the garage for 3 weeks earlier this year and they didnt sort it ,!

 

[Matt Quinn]

Hi matt you will probably hear a very loud cheer if/when i sort this out ,bearing in mind it was at the garage for 3 weeks earlier this year and they didnt sort it ,!

Clucking bell! You'd think the first thing an actual garage would do would be to pull the lift pump and blow through the lines!

- How did the trouble start with yours? ...Any idea what triggered it?

 

[Bantamsteve]

Hi, if I remember rightly ,it started with eml coming on as I was driving ,and not stalling, progressing to where we are now eml coming on ,then stalling ,restarts no problem , but no power ,stalling restart again . And in-between restarting and drives fine. Anyway been to garage today, he's gonna put a new diesel filter on , and check we've got fuel to it ,at required rate , just in case it's blocked , I shall let u know the outcome.,I think we're narrowing it down a bit, albeit frustratingly slow

 

[Matt Quinn]

Ok... so new FPR fitted and it's a no-start. Zero fuel rail pressure (most of the time!) so there is clearly a problem either with what I've fitted or how I've fitted it...

(1) The NEW FPR has (came with) a green 'o' ring fitted as per this picture....

...the OLD FPR had no such ring! Though it does have the relevant slot for one. - Ought the green ring be removed from the new FPR?

(2) The NEW FPR seems to operate in 'reverse phase' to the old one; that is to say it is normally open when not energised whereas the old one was 'normally closed' (and did open when energised with a 12V source).

- I can still hear 'that weird noise' with the engine in the 'on' position and the new FPR in place. I've deduced from the little vague information I can glean from the internet that the FPR is driven by a PWM (Pulse Width Modulation) signal... which means that in operation it should be cycling and presumably that's the sound I can hear. - I wouldn't expect the 'phase' of the valve to make in difference in such a situation (similar things are found in other types of machine) But... does it? Does anyone out there know?

Any thoughts out there?

 

[bugsymike]

Is there a part number on the old unit to compare with new?
Did suppler confirm it fitted your model?
Apart from the hole in the end I see it has holes in the cylinder part so I would assume there would be a need for a sealing ring like the green one to stop fuel escaping to the outside.
However this is assuming it is the same as the old one in design and correct for your vehicle.

 

[Matt Quinn]

Is there a part number on the old unit to compare with new?
Did suppler confirm it fitted your model?
Apart from the hole in the end I see it has holes in the cylinder part so I would assume there would be a need for a sealing ring like the green one to stop fuel escaping to the outside.
However this is assuming it is the same as the old one in design and correct for your vehicle.

Part numbers are different... but I was assured by several different suppliers (including one with a high street presence!) that the "0928400 680" is a direct swap for the 0928400 825 which is now sitting on my desk. - Dimensionally they're certainly the same, the green ring may or may not be a moot point. Both have DC coil resistances of 2.6Ω/2.7Ω... The only difference being one is 'normally closed' (the original) and the other seems to be 'normally open'.

The outer bores are (I'm led to believe) the inlet side the middle one the outlet... I am fairly convinced that the one I've removed is original to the car, and it did emerge from where it had been nestled sans ring. - This makes me question whether the ring is something that is required for some variants and not others; however - there is no fuel escaping.

Out of sheer curiosity I took the ring off and refitted it; this time I was seeing pressure but still no sign of a start... but then after a couple of tries sometimes no pressure. So, whatever this thing is doing, it ain't doing it right!

Not only might I have been mislead over the part numbers; but I do believe this thing to be a piece of chinesium garbage. Tomorrow, when I'm feeling less demoralised, I'll re-fit the old one and see if I can get the car to start and get myself back to square one... at which point I'll order up a genuine Bosch 0928400 825 from a supplier I can actually trace to a UK address!

One thing I've definitely learned from all this is that regardless of company size - the people staffing modern-day parts suppliers aren't like the old-school motor factors and probably aren't even that good at interpreting whatever databases they're looking at; assuming that is they're not just Googling stuff like everyone else!

As I said - I wouldn't normally expect the rest position of a valve to make a difference in a PWM system; but then this is a car engine, not a camera crane - and it's entirely possible the ECU is expecting the thing to be closed when it's open and open when it's closed. - The same pump is fitted to various engines in various guises; and I suppose just because the thing physically fits (and perhaps some ECUs don't care and work fine) doesn't mean it's going to work in every configuration.

I'll see what tomorrow brings.

 

[bugsymike]

Part numbers are different... but I was assured by several different suppliers (including one with a high street presence!) that the "0928400 680" is a direct swap for the 0928400 825 which is now sitting on my desk. - Dimensionally they're certainly the same, the green ring may or may not be a moot point. Both have DC coil resistances of 2.6Ω/2.7Ω... The only difference being one is 'normally closed' (the original) and the other seems to be 'normally open'.

The outer bores are (I'm led to believe) the inlet side the middle one the outlet... I am fairly convinced that the one I've removed is original to the car, and it did emerge from where it had been nestled sans ring. - This makes me question whether the ring is something that is required for some variants and not others; however - there is no fuel escaping.

Out of sheer curiosity I took the ring off and refitted it; this time I was seeing pressure but still no sign of a start... but then after a couple of tries sometimes no pressure. So, whatever this thing is doing, it ain't doing it right!

Not only might I have been mislead over the part numbers; but I do believe this thing to be a piece of chinesium garbage. Tomorrow, when I'm feeling less demoralised, I'll re-fit the old one and see if I can get the car to start and get myself back to square one... at which point I'll order up a genuine Bosch 0928400 825 from a supplier I can actually trace to a UK address!

One thing I've definitely learned from all this is that regardless of company size - the people staffing modern-day parts suppliers aren't like the old-school motor factors and probably aren't even that good at interpreting whatever databases they're looking at; assuming that is they're not just Googling stuff like everyone else!

As I said - I wouldn't normally expect the rest position of a valve to make a difference in a PWM system; but then this is a car engine, not a camera crane - and it's entirely possible the ECU is expecting the thing to be closed when it's open and open when it's closed. - The same pump is fitted to various engines in various guises; and I suppose just because the thing physically fits (and perhaps some ECUs don't care and work fine) doesn't mean it's going to work in every configuration.

I'll see what tomorrow brings.

I generally don't have a lot of problem with Motor Factors once I got them to realise I prefer quality to crap as when I was in business my customers were all regulars I didn't want to let down. Sadly many "mechanics" go for what ever is cheapest these days and often the first option that comes up in a parts search is the item with max. profit margin.
If I buy online I ask the seller if it will fit Reg.No. .... If they say yes and supply wrong it is easier to get redress.
I had trouble getting a correct ABS sensor for a Skoda Scout 4x4 as supplier said only one listed, so I got him to look up a VW Tiguan with the same running gear and low and behold an option was available which was correct.
As an apprentice in 1969 you could throw a part on the store mans counter he would take one look, quote the part number , walk off and return with the correct part. Now if the computer says no that is that!
Going back to your vehicle it seems strange you got some pressure and then not, which may suggest something else is causing a problem.Don't know if relevant but just put the Bosch part number you gave and it shows it without the green O ring, but also on the variety of makes and models it is supposed to fit they all seem to be 1.6 or bigger, I thought yours was a 1.3? Saying all that some of the pattern/chinese ones have the green O ring.
As I say that may be not relevant, apart from that there does seem to be a choice of regulator depending on whether it is the 70hp or 95hp.
I would tend to stick with the type that was working on your vehicle in the first place.
However I am still not convinced that it is the problem. On your high pressure pump is there more than one sensor/control valve, also are you getting any pending or current Error codes on your diagnostic tool.

 

[Matt Quinn]

...No codes at all. And, immediately before removing the old regulator, I started the car from cold to test it was still in the same state I'd left it (after it sitting for nearly three weeks) and found that I was in exactly the same position I had been previously. - Mind you; the reason why there may be no codes at this stage is that the car has not started with the 'new' (680) regulator in place.

For clarity... here is the OLD regulator.

Going back to your vehicle it seems strange you got some pressure and then not, which may suggest something else is causing a problem.

Pressure was obtained on the first two or three starting attempts after the green 'o' ring' was removed, which may have repositioned the FPR - no start. After those two or three attempts it started throwing up 0s again and I just gave up...

Don't know if relevant but just put the Bosch part number you gave and it shows it without the green O ring, but also on the variety of makes and models it is supposed to fit they all seem to be 1.6 or bigger, I thought yours was a 1.3?

Yes... it's a (January - so actually a 2013 model) 2014 1.3 -55Kw - which is 74HP Type 225AXD1A04C

Which of the two part numbers did you look up? And where?

Interestingly THIS Bosch item (with the same part number as the old one) comes with the mystery green washer:

On your high pressure pump is there more than one sensor/control valve

Is there? ...Where?

...Bear in mind that this latest 'no start' fault only occurred once the FPR was changed to something we now suspect is the incorrect part; even though multiple sources (who were actually given the reg no. etc) said otherwise.

If I buy online I ask the seller if it will fit Reg.No. .... If they say yes and supply wrong it is easier to get redress.

I did... and they did... so they're likely to be getting it back.

 

[bugsymike]

...No codes at all. And, immediately before removing the old regulator, I started the car from cold to test it was still in the same state I'd left it (after it sitting for nearly three weeks) and found that I was in exactly the same position I had been previously. - Mind you; the reason why there may be no codes at this stage is that the car has not started with the 'new' (680) regulator in place.

For clarity... here is the OLD regulator.

View attachment 436354
View attachment 436355



Pressure was obtained on the first two or three starting attempts after the green 'o' ring' was removed, which may have repositioned the FPR - no start. After those two or three attempts it started throwing up 0s again and I just gave up...



Yes... it's a (January - so actually a 2013 model) 2014 1.3 -55Kw - which is 74HP Type 225AXD1A04C

Which of the two part numbers did you look up? And where?

Interestingly THIS Bosch item (with the same part number as the old one) comes with the mystery green washer:


View attachment 436356



Is there? ...Where?

...Bear in mind that this latest 'no start' fault only occurred once the FPR was changed to something we now suspect is the incorrect part; even though multiple sources (who were actually given the reg no. etc) said otherwise.



I did... and they did... so they're likely to be getting it back.

I typed in this number 0928400 680 in Google and it came up in an eBay search where it mentioned the two 1.3 engine HPs with the two engine series as a choice.
My daughters was the much earlier 06 1.3 multijet with the lower power 70hp? engine in a Fiat Grande Punto which is different as the pressure regulator was a screw in one on the common rail with no electrical components on the high pressure pump at all, it was also pre all the DPF stuff etc. as one of the first of those models.
I see as you mention your new Bosch regulator appears to have a green O ring also. Some on eBay don't have it but still the same general design.
As yours originally ran happily without that green O ring and no leaks from there presumably it wasn't required, maybe someone else on Forum can advise us.
Just a small thought is it possible that if a bit dry the new regulator with the green O ring bulked up and didn't fit all the way in to it's flange against the pump if view is a bit obscured, I usually put a bit of diesel fuel on the rubber seals or O rings to help fitting? If so it may have affected operation.
Does your injector pump with the pressure regulator fitted/bolted to the end look something like this one, with just the one electrical component on it?
The only one recently I have worked on was a Fiat Scudo that uses a 2 litre Peugeot engine, which has the Siemens injector pump that has a fuel cut off and a fuel pressure regulator on the pump housing.
One final thought , with all pipes and bleeders tight at fuel filter are you 100% happy there is a good air free supply of fuel getting to the high pressure pump as if it is and the fuel pressure regulator is good then it make cast suspicions on the pump it's self, though I would say not common and usually some warning before hand. All the high pressure pipes from the pump/common rail and injectors are tight and dry? As with common rail system if one fitting is not tight or one injector has a leak, even internally then the engine will not start as it will not reach operating pressure.
If that is the case then a "leak off " test would be next.

 

[Matt Quinn]

The fuel pump I have is a Bosh 044 5010 266, exactly similar to this...

...Yes; the sole electrical component seems to be the Fuel Pressure Regulator.

Just a small thought is it possible that if a bit dry the new regulator with the green O ring bulked up and didn't fit all the way in to it's flange against the pump if view is a bit obscured, I usually put a bit of diesel fuel on the rubber seals or O rings to help fitting? If so it may have affected operation.

That's entirely possible yes... it was indeed 'lubricated' with diesel on the way in; but still... With the green 'o' ring in place I got nothing... with it removed I saw pressure come up (as previously outlined) but not consistently or to the degree the engine would fire.

I typed in this number 0928400 680 in Google and it came up in an eBay search where it mentioned the two 1.3 engine HPs with the two engine series as a choice.

...The '680' is what was sold to me as a direct replacement for the '825' that actually came off the car. I now think it's really not.

By repeating your search I've come across a supplier (https://turbo-diesel.co.uk/product/tdvng0087/) who list it for the 95bhp of the Qubo, but not the 75bhp version... The 95bhp version has a different pump ( 0445010 243 as opposed to 266) - Others seem to be careless in their listing practices.

Note too that this supplier - https://injectionpumps.co.uk/product/bosch-cp1h3-measuring-unit-0928400680-used/ - Lists

Bosch CP1H3 measuring unit 0928400680 Fits the following pumps:

0445010150, 0445010155, 0445010156, 0445010157, 0445010183, 0445010184, 0445010185, 0445010193, 0445010202, 0445010204, 0445010241, 0445010242, 0445010243, 0445010247, 0445010248, 0445010249, 0445010255, 0445010256, 0445010303, 0445010305, 0445010311, 0445010321, 0445010394

The pump I have isn't listed there...

PF Jones on the other hand (https://www.pfjones.co.uk/bosch-metering-unit-0928400825.html) confirm the '825' regulator is for the '266' pump.

I see as you mention your new Bosch regulator appears to have a green O ring also. Some on eBay don't have it but still the same general design.

They do all seem to be the same general design... the new/wrong FPR was checked dimensionally and I checked the coil resistance which was pretty-much the same. Apart from the green ring, the only obvious difference is the fact that the new FPR was 'open' (i.e. you could blow through it) when not connected to anything - the 'old/correct' one is closed.

The sound I'm hearing from both the regulators is in the range of about 1Khz and a square wave... i.e. sounds more like a buzzer than a tone. This, I assume is the 'driver' signal from the ECU. - I'm guessing here that since the two regulators seem to operate 'opposite way around' - the 'wrong/new' one might be being commanded to open when it should be closing and to close when it should be opening.

As I say... I think the old FPR needs to go back on (temporarily) to see if that gets us back to square 1; and I probably need to order the correct part from somewhere that has a proper UK trading presence - like PF Jones.

 

[bugsymike]

My background is more the mechanical engineering side of things, you have more knowledge re the electronics of how these regulators operate, however as you say it sounds strange that one is unpowered in the open position and the other not.
Another thought, may be someone on the MES diagnostics side of Forum can advise if these later type regulators need some form of "proxi aligning" or calibrating to operate correctly, but that is a pure guess.
It is easy to go down a rabbit hole, when often there is a simple reason why an engine will not run. When ECUs first came out garages with any fault they couldn't understand immediately blamed the computer which was very rarely the case, more often a sensor or similar, external to the ECU. Obviously if it has water ingress or like one BCM that had been damaged/shorted due to a faulty repair to a poor seat sensor repair that bypassed a resister in the circuit I came across, but not the first option.
Going back to a basic test, more for my peace of mind, with the pressure regulator out of the pump and wiring plug out of the way, but first ensuring nothing inside the pump is loose to drop out, would it be possible for someone to crank the engine to see if you have a flow of fuel coming out at that point, albeit unregulated. You may want to catch it in something, but don't put you hand in the way in case of any high pressures. This would confirm fuel from the tank is coming through the filter and actually reaching the high pressure side of the pump.
Another test with everything connected is to see what volume of fuel is actually returning to the tank from the low pressure "leak off" return side plumbing.
You may need to familiarise yourself with that side of the system, but in simple terms if the pump side, low and high pressure are all working correctly it is still possible for the modern diesel engine not to start due to a fault in the fuel side of the electronic injectors losing pressure due to dirt or wear thereby preventing the common rail reaching operating pressure for the ECU to trigger the injectors.
A simple test is with individual measuring containers connected to the fuel returns from each injector, the engine is cranked or started for a certain amount of time and the fuel collected is then compared for each cylinder/injector, if one is excessively high that would show a faulty injector. There are several videos on line to show how. A kit is available for around £25, but I made one up from screen wash hose and some two stroke mixing bottles I already had.

 

[Matt Quinn]

My background is more the mechanical engineering side of things, you have more knowledge re the electronics of how these regulators operate, however as you say it sounds strange that one is unpowered in the open position and the other not.
Another thought, may be someone on the MES diagnostics side of Forum can advise if these later type regulators need some form of "proxi aligning" or calibrating to operate correctly, but that is a pure guess.
It is easy to go down a rabbit hole, when often there is a simple reason why an engine will not run. When ECUs first came out garages with any fault they couldn't understand immediately blamed the computer which was very rarely the case, more often a sensor or similar, external to the ECU. Obviously if it has water ingress or like one BCM that had been damaged/shorted due to a faulty repair to a poor seat sensor repair that bypassed a resister in the circuit I came across, but not the first option.
Going back to a basic test, more for my peace of mind, with the pressure regulator out of the pump and wiring plug out of the way, but first ensuring nothing inside the pump is loose to drop out, would it be possible for someone to crank the engine to see if you have a flow of fuel coming out at that point, albeit unregulated. You may want to catch it in something, but don't put you hand in the way in case of any high pressures. This would confirm fuel from the tank is coming through the filter and actually reaching the high pressure side of the pump.
Another test with everything connected is to see what volume of fuel is actually returning to the tank from the low pressure "leak off" return side plumbing.
You may need to familiarise yourself with that side of the system, but in simple terms if the pump side, low and high pressure are all working correctly it is still possible for the modern diesel engine not to start due to a fault in the fuel side of the electronic injectors losing pressure due to dirt or wear thereby preventing the common rail reaching operating pressure for the ECU to trigger the injectors.
A simple test is with individual measuring containers connected to the fuel returns from each injector, the engine is cranked or started for a certain amount of time and the fuel collected is then compared for each cylinder/injector, if one is excessively high that would show a faulty injector. There are several videos on line to show how. A kit is available for around £25, but I made one up from screen wash hose and some two stroke mixing bottles I already had.

Thanks Mike... I probably have some old darkroom measures (graduates) in the lock-up that were previously used to measure the tiny weekly oil top ups my old Smart Car used to get. ...And some plastic hose similar to screenwash hose.

The more I dig into this the more I'm finding that there is conflicting information out there on whatever databases the parts suppliers (I won't dignify them with the title Motor Factors) are using. - It does seem to be the wrong part. So, I still think this afternoon (if I get time) I need to re-fit the old regulator and see if it starts... that would tell us a few things.

 

[bugsymike]

If able to do some of those things I suggested it may help narrow down a little.
I would start from the supply end and finally the injector leak off test. Mike

 

[Matt Quinn]

If able to do some of those things I suggested it may help narrow down a little.
I would start from the supply end and finally the injector leak off test. Mike

Well... bear in mind the journey so far...

(1) Lift pump replaced - following the frozen fuel debacle.

(2) Fuel filter replaced

(3) Left sitting for a few days (due to circumstances) with a mix of winter fuel and injector cleaner the car went from constantly cutting out (with the new lift pump and filter) to starting relatively easily and idling/revving. - As if the cleaner had cleaned something!

A few minutes ago I took the 'new' FPR out and replaced it with the original... the car then started without much fuss; was run for a few minutes etc. - So I am (thankfully) back in the position I was; and I think we can safely say that the cause of the non-starting was the incorrect Fuel Pressure Regulator.

I've now ordered the correct Bosch item 0928400825 - which I hope to have in my hands in the next day or two. - With this particular setup; that FPR is actually the final stage of the low pressure or what we could call the supply end. ...And the overall process has been to try and ensure the supply/LP side of things is clear before moving on.

 

[bugsymike]

I may be wrong but as I understand it the fuel pressure regulator is on the high pressure side of the pump and allows pressure to "bleed off" or not into the fuel return circuit by use of the holes in the regulator controlled by the ECU to regulate from a starting pressure of around 300 Bar up to and in some cases above 2000Bar. Lets hope you get a good result from the new regulator.

 

[Matt Quinn]

I may be wrong but as I understand it the fuel pressure regulator is on the high pressure side of the pump and allows pressure to "bleed off" or not into the fuel return circuit by use of the holes in the regulator controlled by the ECU to regulate from a starting pressure of around 300 Bar up to and in some cases above 2000Bar. Lets hope you get a good result from the new regulator.

That would definitely appear to be the case where you have the regulator on the fuel rail... and this may well be where much confusion is arising.

BOSCH CP1 interactive parts diagram - Diesel Injection Pumps

Common Rail Injection System Pressure Control

This (such as it is) seems to concur exactly with what you suggest.

...However other sources suggest that 0928 400 825 is:

Function	Control Valve, fuel quantity (common rail system)
Placement on Vehicle	High Pressure Pump (low pressure side)

And it's commonly described as an inlet metering valve... fuel metering valve... etc.

Then there's this: relevant because it's describing a CP1H pump. https://www.manualslib.com/manual/1110450/Alfa-Romeo-159.html?page=146#manual

"A low pressure regulating solenoid valve is fitted on the pump inlet to adjust delivery pressure and compress only the fuel needed to each the pressure mapped in the ECU."

...So, not always on the high pressure side; it seems there are perhaps two approaches and two possibilities!

Getting clear information on this seems like a case for Mulder and Sculley! What little there is out there seems to be in Eastern European or South Asian languages - is often contradictory (where it can be translated at all) and is mostly trying to flog stuff!

It's little wonder the parts suppliers are so confused.

 

[bugsymike]

That would definitely appear to be the case where you have the regulator on the fuel rail... and this may well be where much confusion is arising.

BOSCH CP1 interactive parts diagram - Diesel Injection Pumps

Common Rail Injection System Pressure Control

This (such as it is) seems to concur exactly with what you suggest.

...However other sources suggest that 0928 400 825 is:

Function	Control Valve, fuel quantity (common rail system)
Placement on Vehicle	High Pressure Pump (low pressure side)

And it's commonly described as an inlet metering valve... fuel metering valve... etc.

Then there's this: relevant because it's describing a CP1H pump. https://www.manualslib.com/manual/1110450/Alfa-Romeo-159.html?page=146#manual

"A low pressure regulating solenoid valve is fitted on the pump inlet to adjust delivery pressure and compress only the fuel needed to each the pressure mapped in the ECU."

...So, not always on the high pressure side; it seems there are perhaps two approaches and two possibilities!

Getting clear information on this seems like a case for Mulder and Sculley! What little there is out there seems to be in Eastern European or South Asian languages - is often contradictory (where it can be translated at all) and is mostly trying to flog stuff!

It's little wonder the parts suppliers are so confused.

Thanks for the details on web sites, it makes interesting reading.
So am I correct, depending on what pump and system used you could have just a low pressure metering valve on the pump and a actual Fuel Pressure Regulator elsewhere , possible on the Common Rail or a regulator valve on the pump that does everything,. Meaning it is critical pump and valves are correctly identified.
Can you enter the full pump details from yours online to see how yours should correctly function?
On the Fiat Scudo I have the high pressure Seimens pump has two separate control valves mounted on the pump, so different again, also and not so good it uses the high pressure pump to "suck" the fuel from the tank in the first place with no pump in fuel tank.

 

[Matt Quinn]

...It's been driving me nuts Mike; trying to get information I mean.

Here's the label on the side of the pump...

That part number - along with the car's registration number - was given to various parts suppliers when I was looking for the regulator (which I was eventually mis-sold). - You can see yourself it's a CP1H3 pump... I've googled it 'every which way'... The nearest I've come to an explanation is that link to the Alfa manual and the oft-repeated notion that the regulator works (is the final stage effectively) on the LP side...

Which is duly contradicted by that second diagram in the 'paywalled' paper on dieselnet!

In general the lack of information for this car is something I'm finding frustrating to the point that when I get it sorted out it might cause me to decide to move it on and get something else.

...I'm old enough to be of the generation of cameramen where they first trained you basically as an electronics engineer (in a very specific/specialised area). That training included what we'd now call 'mechatronics'; dealing with the very complex video recorders (a world away from your domestic VCR) that were used in broadcast; as well as the complex systems used in automated camera rigs, cranes etc.

I've also been mucking about with old cars since I was about 14! - Which was 47 years ago! Once completely rebuilt a Morris Minor as well as modified and rigged numerous camera cars and OB units and have generally run weird things been unafraid to get my hands dirty. - I once owned a Porsche 924 with its 'wondrous' mechanical fuel injection system - which never aged well for anybody! But then; at least I could get the information and get the thing going!

Every instinct - and all my training as well as experience (professional and otherwise) -tells me to follow a logical sequence; clear one hurdle before attempting the next...

The one thing I didn't do was just 'wade in' and change the pressure regulator off the back of what my old VW scanner told me at first; in fact once the car apparently started to settle down; I would rather have avoided removing the thing at all. - Even though (I thought) I had a replacement sitting on my desk. - I've followed a logical sequence from finding the lift pump was (apparently) damaged after the thaw etc. Got another scanner, tried to use the (admittedly limited; it too is chinesium crap!) data it's giving me etc.

I really don't understand how some temporarily-waxed fuel could cause the damage it seemingly did... but the thing that's really frustrating me at every turn with this car is the complete lack of information; with what can be gleaned (even by people in the trade) being sparse and often contradictory. ...Even this 'hill holder' crap which I'll need to deal with at some stage because the message in annoying me; a seemingly common fault which nobody really seems to be able to point at and explain what causes it or how to fix it.

...At this stage I'm not even sure how 'angry' to get at the people who mis-sold the wrong regulator; because I can see exactly how the conflicting information that is out there might cause them to do so! - Ebay's parts system (in common with Europarts and a few others) doesn't even differentiate between the 95hp and 75hp versions!

...There's a very nice fully restored and fettled Morris Minor van sitting down near Halifax that would do me fine... Pity they want the sharp end of £20K for it; but at least if that went wrong I could piggin' fix it!