2.5 DHSE loss of power & low MPG

My 2001 2.5 DHSE over the last few months has been losing power whilst MPG has fallen from an average of high 20's to low 20's (with A/C off), I've owned it for over 3 years and it has a PSI Powerbox fitted.

It now struggles up hills it used to go up without problems and overtaking is a no no.

I am due to pull my caravan with it next month but it struggles to pull itself at the moment!

Any sensible suggestions as to what could be wrong with it are welcomed

Fuel filter and air filter been changed recently?

Yes, both changed only 2 weeks ago, made no difference.

could be fuel filter as Datatek, or fuel pump getting lazy, what mileage is on it? but it could also mean turbo problems/failure. Check all the turbo hoses or any signs of oil in or around the turbo.

Ever cleaned the intercooler out ?

Cars done 85,000, no signs of oil around turbo, hoses look OK, slight bulging on all rubber turbo hoses when engine revved.

Intercooler cleaned out about 4 months ago when I had to replace the engine oil cooler due to an oil leak.

Grange Grover said:

Cars done 85,000, no signs of oil around turbo, hoses look OK, slight bulging on all rubber turbo hoses when engine revved.

Intercooler cleaned out about 4 months ago when I had to replace the engine oil cooler due to an oil leak.

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Have a look at connections to MAP sensor or sensor it'self. Also EGR valve.

Hi Grange Grover
I appreciate that you emailed me re something related to my answer below, that I put in a recent post, but I found "message undeliverable" when I tried to email back to you.

Here's a synopsis of what I tried to send: regarding that piece of pipe that comes up vertically from the right-hand side of the engine (left if facing the bonnet). I understand that it produces a hot air/vacuum into the inter cooler. It consists of three pieces (i) a roughly 'L' shaped hose (2 inches diameter) that connects to (ii) an metal piece of pipe, about 12inches long, then into (iii) a 3 inch length of hose that connects to the intercooler.

Part (i) is not an 'L' of equal leg lengths - the longer leg comes up from the engine with the shorter leg connecting with the alloy pipe (ii). There being two hose sections in this whole component there was enough flexibility, for my emergency repair, to reverse the 'L' and fix the cleaner (non-split) piece to the engine take-off: leaving the opportunity to cut off the split (and part perished piece) and still have sufficient to join up again to section (ii).

It's awkward to get at, but I think this piece of 'L' shaped pipe needs to be taken off and inspected regularly as a matter of course, because it's absolutely impossible to do so with any certainty whilst it remains in situ and it's essential that there are no leaks in this. Mine had actually come free from what is a very short collar near the engine and was still difficult to spot. The loss of power and increased mpg were both significant until this was fixed.

Main agents claim that all three sections come as one component piece - 123 quids! All it requires is a short 2" hose with a 90 degree bend, which is relatively easy to source.

Any way, I hope this is helpful and it would be nice if this was the cause of the problem for you. I know I was relieved to find that this is all it was.
DougK

Grange Grover said:

My 2001 2.5 DHSE over the last few months has been losing power whilst MPG has fallen from an average of high 20's to low 20's (with A/C off), I've owned it for over 3 years and it has a PSI Powerbox fitted.

It now struggles up hills it used to go up without problems and overtaking is a no no.

I am due to pull my caravan with it next month but it struggles to pull itself at the moment!

Any sensible suggestions as to what could be wrong with it are welcomed

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AUTO or MANUAL ?????

the hooded claw said:

AUTO or MANUAL ?????

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Claw it sounds like his turbo is not working or if it is the MAP sensor is fault air leak to it, or EGR valve is not working properly. Or a combination of both. The vehicle is obviously not fueling properly.

wammers said:

Claw it sounds like his turbo is not working or if it is the MAP sensor is fault air leak to it, or EGR valve is not working properly. Or a combination of both. The vehicle is obviously not fueling properly.

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My thoughts were goin down another DMF route Tony .....Lumpy Tickover No Power High Fuel comsumption ...Ect Ect ...........

the hooded claw said:

My thoughts were goin down another DMF route Tony .....Lumpy Tickover No Power High Fuel comsumption ...Ect Ect ...........

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Lumpy tick over sounds like EGR valve stuck open. DMFs are bloody stupid things but cannot as far as i am aware cause power loss or **** consumption. Once the clutch is engaged they just spin around with the rest of the flywheel a little loosely maybe. They are only like a cush drive that absorbs the surge of torque as each piston fires at low RPMs in high gears. At normal road speeds they are of little value and do absolutly nothing at all.

Update:

Car is Auto and tick over is fine.

Haven't checked the pipes DougK suggests yet (assume the lower 2" pipe is the one which connects directly onto the Turbo?).

Renewed the pipe to the MAP sensor which appeared OK this made no difference.

However spoke to the PSI Powerbox people about what the green & red LED's should be doing inside the powerbox. After speaking with them they came to the conclusion the box was not behaving properly and requested that I send it back to them in Luxembourg, which I have done.

I am now riding around with no Powerbox on it and the MPG and power is about the same as it was with it connected!!!!!

Will let you know what the PSI people say/do.

PSI Powerbox returned from Powersport and was said to be OK but out of adjustment.

Re fitted to car, no difference.

Now believe fault to be the in tank lift pump, will replace and update.

Grange Grover said:

PSI Powerbox returned from Powersport and was said to be OK but out of adjustment.

Re fitted to car, no difference.

Now believe fault to be the in tank lift pump, will replace and update.

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from your first post i have recently had a similar problem. when trying to go up hills or overtake the power would just not be there and would struggle like anything!

i changed my map sensor and renewed the pipe which goes from the map sensor to the underside of the inlet manifold and all was ok, i know you have said that you checked this pipe but i might just say that when i checked mine it seemed ok until i took it off and it split in half!

Tommo138 thanks for your post, I did replace the pipe even though it appeared OK on inspection, just to be sure.

Where did you get the MAP sensor from and more importantly at what cost!

Thanks

I had the same symptoms as you a year or 2 back, tried all the 'usual', ended up replacing the in-tank pump, cured the problem & running fine since!

modelman said:

I had the same symptoms as you a year or 2 back, tried all the 'usual', ended up replacing the in-tank pump, cured the problem & running fine since!

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funny you said that i had the same problem this year changed me pump in the fuel tank .was sound as apound after ..........

Grange Grover said:

Tommo138 thanks for your post, I did replace the pipe even though it appeared OK on inspection, just to be sure.

Where did you get the MAP sensor from and more importantly at what cost!

Thanks

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this should help:
SENSOR-TURBO BOOST

if you do decide to change the sensor i hope it cures your probem.

Sorted............

I changed the in tank fuel pump, using Canyon's excellent through the floor method, from his template thread.

The car's "performance" has been restored and I am now getting an average of 30 to the gallon, best it's been for about 18 month's.

Wish I had changed it before, but had difficulty believing the car would still run how it did with a duff pump.

For info with an amp meter across the pump fuse the new pump now draws 4.5 amps.

A big thanks to everybody for your help, and especially to Canyon for saving me time & grief with his "through the floor" method of tank pump replacement.