got a 90 that was running fine, but is now well down on power, the turbo's spooling up (I can hear it working normally) but it's making no difference to the engine power

I've checked the intercooler pipes - no splits
checked the breathers to turbo/dump valve - no blockages or splits

could it be the dump valve stuck? or am I missing something obvious

Cheers

Hi Corby,
You don't mention the actual vehicle, so i'm just guessing.
I'm no expert but figured i might as well kick it off. . .
I'm none too clever with turbo's, but i thought the dump valve opened to get rid of excess boost, so you don't ruin the engine; presumably if it was stuck open the turbo wouldn't then be spooling up correctly? I'm probably wrong- hopefully someone will put me right.
It it was me i'd check the fuel system too.
Have you checked the fuel filter, fuel lines etc? Lift pump fault could also be involved. If you're running a tdi with a genuine lift-pump (unlikely, but still), there can be an internal filter (screw on the top of the pump) that gets clogged with rubbish. Also do you run it on Diesel or throw in some Veg oil/biofuel as well- if veg oil is involved it can clog filter much more quickly, but you only notice when engine is under load- tick-over is usually fine.
How smooth does the engine run under acceleration?
Also is there any smoke during tick-over and acceleration?

As i say i'm not an expert and i'm usually wrong about most things. . .

Good luck!

hi Steve, it's a 200tdi, I've changed the fuel filter since it's started playing up, no change.

it runs fairly normal on the flat, but give it a slight slope and it's slow down and change down time

as for dump valves, I'm not 100% sure about them but you sound right

how do I check the lift pump? sorry for the silly questions but I'm still learning


ooops nearly forgot, running it on normal diesel, no veg oil etc

Hi
Sounds like you've done a lot of the obvious things. It also sounds like a problem i've had/am having with my 200tdi 110. Mine seems to have been getting gradually slower over the past few months- but only noticed when i took it out with some other defenders who left me standing- and i have experienced exactly the same as you in terms of hills. I've been advised on here and by a Garage that it could be down to a worn lift pump (they're not the most reliable units anyway). I'm not sure how to test them- there is a manual priming handle on the pump that may give tell tale signs of wear, but i'm not sure to be honest as i've not got around to replacing mine.
Good news is that a new pump is only about £15-£20 and it's useful to have a spare so if it isn't that it won't be wasted in theory. . .

If you've not encountered a lift-pump before, here's a Buster guide to replacing it- it'll tell you where to find it if nowt else.

http://www.landyzone.co.uk/lz/f41/fuel-lift-pump-removal-renewal-63788.html

Hope this helps a bit!

I'll have a look see if it's got any obvious play in the priming handle, but at that price I'll have a run over to Paddocks in the morning and change it anyhow

thanks Steve

hello mate.

i had the exact same problem! going up a hill i would be dropping down into second and sometimes i would even be in first. i changed my filters and lift but an it made no difference. i took it to a garage and he checked my injectors and there was air in my system, after we check that so some reason the problem half fixed its self. there was also someone ells who was having the same problem think his name was "POS" i think he replaces his injectors and he fixed the problem.

http://www.landyzone.co.uk/lz/f7/extreme-power-loss-125009.html

thread might help a little

good luck

Ben

thanks Ben, I'll try the lift pump first (it's cheaper) but it gives me some more ides

cheers

corbydog said:

thanks Ben, I'll try the lift pump first (it's cheaper) but it gives me some more ides

cheers

Click to expand...

To try the lift pump. I think you unscrew the banjo bolt on top of the fuel filter until you can see the samll hole, then operate the lift pump handle, this is how you prime the fuel filter, and if no fuel comes out after a while then your lift pump might be trash

Hope this helps
Dave