P38 low power pulling off? After lots of work?

Hello
This is my first post so sorry if it's in the wrong place.
I have a p38 D and it started to lose power about 4 months ago especially pulling off, a so called specialist recommend a new gear box (auto), which it now how's as well as the initial problem
She has just had the main D pump stripped and reconditioned, along with the rear one, plus injectors cleaned and reset, but still have problem.
Diagnosis shows nothing.
Basically if on any hill or under load she wil not move, in fact you have to engaged neutral increase to 2000+ rpm and drop in drive to get her rolling ( interesting at roundabouts). Once above this rpm she will pull but has exssive fuel consumption, and the throttle is open a lot further than normal to maintain a constant speed, please can anyone help, thank you

Check the security and free flow of the small 6/7mm dia. pipe from under the manifold to the MAP (Manifold Absolute Pressure) sensor mounted on the fuel filter....

This tells the ECU the Turbo Boost pressure and can get gunked up or split....

Another check would be the intercooler....might need a clean, also check the Turbo pipes are collapsing or delaminated internally.

Do you have good drive if you manually select 1st then once moving, select Drive?

what year is it? does it have an air flow meter from late 98 on engine management system changes will help to diag the fault

Hi, thanks for you replies, the vehicle is a 2001, and I'll go and check those small pipes now, I have a feeling the last garage replaced them, is there an easy way to check the internals of the turbo pipes as suggested?
Also can I check the inter cooler in place ?
Regards

2perry said:

Hi, thanks for you replies, the vehicle is a 2001, and I'll go and check those small pipes now, I have a feeling the last garage replaced them, is there an easy way to check the internals of the turbo pipes as suggested?
Also can I check the inter cooler in place ?
Regards

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As it's a 2001, you need to check the EGR valve and the MAF.
Remove the pipes to check for splits, remove the intercooler, and wash out with acetone or some other solvent.

one of the last then! as there are no fault codes present my first item to look at would be air flow meter or maf if it has completely failed would give those exact symptoms.
easy check just disconnect it and take it for a drive and see if it improves, it is located between air filter box and inlet manifold on the air intake pipe.
if there is a marked improvement renew it but only use genuine or oem not sure if it is pierburgh or bosch cheap ones never work properly or last.
if there is no improvement remove and blank egr valve but normally with those symptoms i would be looking straight at the maf

Hi again,
Ok, the EGR value was removed and a blanking kit fitted by myself about a year ago now.
The previous garage have assured me they tried a new air mass flow sensor (think that's correct) and found no change, I have now checked all the fore mentioned pipes all appear to be present and correct, I have also just removed the air intake system and checked all internals, the only thing in all was an amount of oil which appears to be being blown out of the rocker cover vent into the system, I ran the engine and there does appear to be quite a lot of crank case pressure and oil was being thrown out of the oil filler cap at the time, starting to wonder if I have worn bores or broken rings maybe?? Car has 102k on clock. Does this help anyone thanks

Saint V8, reply to last question no problem in any gear as now have new box, but old one was the same, drives in all selections thanks.

2perry said:

Hi again,
Ok, the EGR value was removed and a blanking kit fitted by myself about a year ago now.
The previous garage have assured me they tried a new air mass flow sensor (think that's correct) and found no change, I have now checked all the fore mentioned pipes all appear to be present and correct, I have also just removed the air intake system and checked all internals, the only thing in all was an amount of oil which appears to be being blown out of the rocker cover vent into the system, I ran the engine and there does appear to be quite a lot of crank case pressure and oil was being thrown out of the oil filler cap at the time, starting to wonder if I have worn bores or broken rings maybe?? Car has 102k on clock. Does this help anyone thanks

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Did you actually remove the turbo pipes to check? Hard to spot splits/internal delamination in situe.
Oil in the pipes and intercooler is normal.
Worth checking the oil seperator/breather from the rocker cover is OK

6704 N just to be 100 percent unplugged AMS as recommended and yes that is exactly what she was like before I had all fuel bits serviced, runs much better with it plugged back in and appears to be a new unit as the garage said. Their moods have made a vast improvement but she is still way down on power and drinking juice?

Datatek
If you are referring to the turbo pipes on the air intake side, yes I removed and inspected with a torch, there were two soft couplings with metal piece in between if that's the right bits? Thanks

2perry said:

Datatek
If you are referring to the turbo pipes on the air intake side, yes I removed and inspected with a torch, there were two soft couplings with metal piece in between if that's the right bits? Thanks

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To the turbo and from the turbo to the intercooler, then from the intercooler to the inlet manifold all need to be checked.

Datatek, yes removed all those this afternoon up as far as EGR blanking kit, so from air filter to there, I think I got them all

2perry said:

Datatek, yes removed all those this afternoon up as far as EGR blanking kit, so from air filter to there, I think I got them all

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I would go with the other suggestion that it's the MAF then, it may have been replaced, but if it's a cheapo it may be NBG. Really needs diagnostics and live data to see whats going on.

The MAF is an oem new part, and she performed the same with old one, have been through two lots of diagnostics and she shows nothing hence all the head scratching, really apreciate all the posts if anyone knows of a good guy near Bedford please share thanks

The main function of the MAF on the diesel is to control the EGR. It has little effect on anything else.

Did you check the little pipe from under the manifold to the MAP? This does split and/or get gunked up....

Also if the MAP is playing up this could be another thing to check.

Are you getting good fuel flow through the clear pipe from/to the filter....i.e. no air bubbles present, as this could indicate a weak in tank pump.

Getting the live data read will the engine is running will qualify the injection timing is correct, the MAP is reading the right pressures and the MAF is functioning....

A Diesel is fairly basic, it just needs the right amount of fuel injected at the right time.....as there is no throttle, the Air/Fuel mix is pretty much set, the only difference that will affect the fuelling map is the Manifold Pressue (MAP Sensor).....

But I am not a Diesel expert....others are much more knowledgable...

Hello again, I've taken her to a old school guy in dirty blue overalls, and he has had this problem before and is leaning towards a stretched timing chain, which he will check next Tue if I take car back, does this ring any bells with anyone thanks.

Is it difficult to start? Stretched timing chains tend to make the engine not want to start, when u had the diagnostics done were they just looking for fault codes or were they checking live data?

She can be hard to start when warm, which the guy said is a sign for the chain, can't be 100 percent with what they checked on diag, again this new guy said that the ecu can say that the fuel timing is correct however the mechanical link may not be, sounds logical to me, Thanks for your reply