2.5 - lack of low down grunt

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dogsbody

dogsbody

Very senior member
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10,678
Location
Bristol
My 2000 2.5 diesel Rangie has got no go until I hit about 2,200 rpm and, I assume, the turbo kicks in.

Once she's rolling she's quite happy unless I hit a long hill like the M6 over Shap or Haldon/Telegraph south of Exeter when she gets a bit reluctant, and the temperature gauge rises out of the blue. I suspect that she hasn't got a stat but that's for another time as I want to service the heater, flush out the rad and replace the water pump all at the same time, when the weather's a bit warmer.

She's been fully serviced, all the fluids and filters have been changed and she's got a new in-tank fuel pump.

There is a PSI box on it (it was there when I bought it) but I believe that it's an older version as it has a link into a vacum pipe. There's no great difference whether this is connected or not.

I thought that I'd learn to live with this but having this sudden burst of power when I was recently pussyfooting over hard packed snow in Kent made me realise that I've got to do something before I head for Perth for Hogmanay.

So, will a new PSI box give me the missing torque? Or is there something else that I'm missing?
 
dogsbody said:
My 2000 2.5 diesel Rangie has got no go until I hit about 2,200 rpm and, I assume, the turbo kicks in.

Once she's rolling she's quite happy unless I hit a long hill like the M6 over Shap or Haldon/Telegraph south of Exeter when she gets a bit reluctant, and the temperature gauge rises out of the blue. I suspect that she hasn't got a stat but that's for another time as I want to service the heater, flush out the rad and replace the water pump all at the same time, when the weather's a bit warmer.

She's been fully serviced, all the fluids and filters have been changed and she's got a new in-tank fuel pump.

There is a PSI box on it (it was there when I bought it) but I believe that it's an older version as it has a link into a vacum pipe. There's no great difference whether this is connected or not.

I thought that I'd learn to live with this but having this sudden burst of power when I was recently pussyfooting over hard packed snow in Kent made me realise that I've got to do something before I head for Perth for Hogmanay.

So, will a new PSI box give me the missing torque? Or is there something else that I'm missing?
Click to expand...

If you have a power box fitted and the performance is not good. Maybe it is duff. BUT. Maybe also it was fitted just to glaze over a problem. You have to get the engine sorted BEFORE you fit one, not just fit one to a tired or badly maintained motor. Many people fit these and to be honest it's like sprinkling icing suger on a turd unless the engine is right first. Clean out the intercooler. Check the turbo hoses. Check the pressure pipe to the MAP sensor is sound and sensor itself. Check the fuel lift pump is working properly. Change air filter/fuel filter. Get the injectors serviced. Get the engine running as well as it can before fitting a power box then you may notice a difference.
 
Blank the egr pipe with a 1p or 2p. That has helped my 99 DSE with lowdown torque. looking at a decat next and have ordered an ITG filter to go inside the airbox. I don't have a power box and yes it does need 1500 to 2000 to get going.
 
As Wammers says get your problems sorted before any tweaks, plus if your engine has no thermostat do that NOW! Running cold increases fuel consumption, increases engine wear and decreases power. I agree with Dean that the engine does need a good few revs to get going, tis the way it is.
 
None of them have got any power below 2200/2500 rpm with or without a power box fitted, read the threads about the ones with a manual box to see how bad they can be.
If yours is auto, stick some lead in your right boot and drive round the problem, with a decent amount of throttle opening the torque convertor slip allows the engine to get into the power band from a standstill, then it goes, at least mine does.
 
Thanks to you all.

Apart from blocking the EGR or swapping it for a V8 I've already done all of the suggestions.

Sod it, it's still worth it just to look down on almost every other driver.
 
I think in an ideal world we would all like a cheaper to buy v8 but in reality the mpg and engine issues of the 4 and 4.6 made me buy the 2.5 diesel which still goes very well. Yes LPG is good but that slipped liner issue!
 
dogsbody said:
There is a PSI box on it (it was there when I bought it) but I believe that it's an older version as it has a link into a vacum pipe. There's no great difference whether this is connected or not.
Click to expand...

Just my .02€:
I've got the same PSI powerbox, the one that taps into the MAP sensor pipe. By option, I'm currently running with it disconnected, but it does make a very big difference, especially at the rev range just before the turbo, say 1.200rpm to 2.000rpm. Yours is probably dead or you have a bigger problem with the engine.
 
I disconnected it to see what mileage i get and to be able to compare it directly to the onboard computer's result. Unfortunately, due a set of mishaps, I haven't done more than two full tanks with the box disconnected, so I don't have that much info to compare.
I know that some will find this strange but I'm happy with the Rangie's performance without the box, since I'm perfectly comfortable with it not being a race car :)
 
Last edited:
hi there ive just had exactlythe same issues with mine it turned out to be the battery so do a quick check on your battery and also your alternator.let me know how you get on.
 
azzd said:
hi there ive just had exactlythe same issues with mine it turned out to be the battery so do a quick check on your battery and also your alternator.let me know how you get on.
Click to expand...

When my alternator went, one of the problems was the fuel pump not working. Performance was rubish and, as soon as the alternator was refurbished, it came back to it's usual self. Still not a race car though :D
 
im new to this just had my 93 dico wrote off decided to buy a 96 p38 think i bought a bit of a dog, but sorting it, it is a bit gutless so got some big boots now, makes it go a bit qiucker, must admit i do feel a bit upper class driving it, ****ed me off when my missus overtook me in her maverick, have to disconnect her turbo or somthing, cant be doing with that
 
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