300tdi no power/grunt? Another thread i know

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ONE LIFE LIVE IT. D90

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Hi,

Yesterday i had to tow a small quad trailer around some country lanes, the total weight of everything on the trailer would have been no more than 650kg. I expected the 300tdi to not even notice pulling that weight, but to tell the truth, it struggled. Hense posting this thread! I was having to drop down into second gear and thrash it, just so it would even slightly pull in 3rd gear (labouring).
Then i came to pull the trailer offroad up a slight hill. And i had to use 1st gear low range. Which despite low range probs being the best thing, really indicated to me how down on power it was.
There is not a chance it would successfully pull a heavy farm trailer!

The power loss has come to my attention recently, (owned a few months) and i thought the lift pump was suspect. So i cracked off the bleed screw on filter housing and no diesel was present, but ive checked the outlet pipe to the filter housing and diesel is present. So presume the lift pump is working. I tested it by cranking the engine.

Its got all new filters on 500 miles ago and a service.

I dont think there any intake leaks as it stalled when sealing up the snorkel head. Ive also removed and inspected all turbo to intercooler pipes and i cant see any issues.

The turbo can be heard spooling up or sucking. (Safari snorkel). Its fairly significant sound

It doesnt smoke much at all, theres a big puff of black smoke on start up, and thats it really. Ive been told by someone behind that it never smokes. All though in headlights ive noticed smoke when accelerating hard. But not bad!

No brakes are binding

Any help would be greatly appreciated. Ive searched and ruled out possible causes as a result, but dont know where to go from here.

Thanks
 
either fuel or air.

test lift pump, checking fuel squirt amount incase of a clog
change filters
check pump hasn't been touched
check it's not a veg mix for testing
check pipes for leaks again
check intercooler for leaks/oil spots
check egr hasn't caked intake up
check air filter
check turbo actuator isn't seized open and is working
check tube from turbo to the inj pump is good

post back :)
 
either fuel or air.

test lift pump, checking fuel squirt amount incase of a clog
> ive removed the outlet pipe from the lift pump, unplugged wire on fuel injection pump and tested if diesel is pushed out and it is. Is that correct?

change filters
> all new filters 500 mile ago

check pump hasn't been touched
> how can i check that?

check it's not a veg mix for testing
> veg fuel mix you mean? And no totally diesel

check pipes for leaks again
> intercooler to turbo pipes have been removed, look okay to me

check intercooler for leaks/oil spots
> no signs of leaks round the intercooler

check egr hasn't caked intake up
> mines a 95, has no EGR

check air filter
> thats also new

check turbo actuator isn't seized open and is working
> how do i check this? Will investigate

check tube from turbo to the inj pump is good
> will have a look at this, am i looking for holes?

post back :)


Thanks for the replies
 
it's not confusing.. did the job :)

test lift pump, checking fuel squirt amount incase of a clog
> ive removed the outlet pipe from the lift pump, unplugged wire on fuel injection pump and tested if diesel is pushed out and it is. Is that correct?
sounds good to me, you cranked the engine and got the fuel pumping?

change filters
> all new filters 500 mile ago
depends if crud is in the tank.. but meh should be ok. also check fuel hoses, esp around the tank for leaks

check pump hasn't been touched
> how can i check that?
usually scratches or a missing cap.. just look to see if it's been touched before

check egr hasn't caked intake up
> mines a 95, has no EGR
i wasn't aware 95s didn't have them :)

check turbo actuator isn't seized open and is working
> how do i check this? Will investigate
if you have an air line, pull the hose from near the turbo that goes to it. fire 16psi down and you should see something move.

or you can have a peek and feel for the arm, it's tough but you can move it.. maybe with some pliers.

ofc a better way would be to have a boost gauge, if it was stuck open you'd have hardly any boost :)


check tube from turbo to the inj pump is good
> will have a look at this, am i looking for holes?
yeah, splits. as the pressure builds from the turbo the air goes down that pipe to the pump and moves a diaphragm which increases the fuelling to compensate for the extra air


imo, it sounds more like fuelling to me.. not enough go go juice.. as even without boost it should still go up the hill.. though slowly..so it could be the lift pump even if you get a half decent squirt.

if it's old, then it's worth replacing anyway.. i also stick an inline diesel filter just before it to catch any crud. delphi are regarded as a good one to get.

oh, and check for and the fuel lines haven't got kinked or something.. and on the air side the internals of the hoses haven't de laminated and causing a blockage (though i doubt it in this case) :)
 
Last edited:
it's not confusing.. did the job :)

test lift pump, checking fuel squirt amount incase of a clog
> ive removed the outlet pipe from the lift pump, unplugged wire on fuel injection pump and tested if diesel is pushed out and it is. Is that correct?
sounds good to me, you cranked the engine and got the fuel pumping?

change filters
> all new filters 500 mile ago
depends if crud is in the tank.. but meh should be ok. also check fuel hoses, esp around the tank for leaks

check pump hasn't been touched
> how can i check that?
usually scratches or a missing cap.. just look to see if it's been touched before

check egr hasn't caked intake up
> mines a 95, has no EGR
i wasn't aware 95s didn't have them :)

check turbo actuator isn't seized open and is working
> how do i check this? Will investigate
if you have an air line, pull the hose from near the turbo that goes to it. fire 16psi down and you should see something move.

or you can have a peek and feel for the arm, it's tough but you can move it.. maybe with some pliers.

ofc a better way would be to have a boost gauge, if it was stuck open you'd have hardly any boost :)


check tube from turbo to the inj pump is good
> will have a look at this, am i looking for holes?
yeah, splits. as the pressure builds from the turbo the air goes down that pipe to the pump and moves a diaphragm which increases the fuelling to compensate for the extra air


imo, it sounds more like fuelling to me.. not enough go go juice.. as even without boost it should still go up the hill.. though slowly..so it could be the lift pump even if you get a half decent squirt.

if it's old, then it's worth replacing anyway.. i also stick an inline diesel filter just before it to catch any crud. delphi are regarded as a good one to get.

oh, and check for and the fuel lines haven't got kinked or something.. and on the air side the internals of the hoses haven't de laminated and causing a blockage (though i doubt it in this case) :)


Thanks a lot trax for your in depth replies.

Regarding the lift pump, there was diesel present when i removed the fuel pipe to the filter housing, but it wasnt squirting out under a lot of pressure. It was just a pulse of diesel.

For the sake of a the cost of a fuel filter I'll try one of those. Pipes from the tank look in good condition, its a new tank a couple of years ago too.

I'll check the other things youve suggested.

It starts and runs great in general. It just seems to struggle under load, and anything other than the perfect gear it labours. And country lanes with little weight requires a low gear and high revs. Which im not a fan of revving it highly!

Thanks again
 
I say the lift pump was working through the pipe i removed to the filter housing, but how come work there wasnt anything coming out of the bleed screw when i slackened/removed it. Granted i havent tried it manually, and both methods tried by cranking but assumed cranking the engine over shows the best chance of the the lift pump working?
 
I say the lift pump was working through the pipe i removed to the filter housing, but how come work there wasnt anything coming out of the bleed screw when i slackened/removed it. Granted i havent tried it manually, and both methods tried by cranking but assumed cranking the engine over shows the best chance of the the lift pump working?

show's it's working cam side anyway.. nothing coming out of the fuel filter bleed screw?

if you crack that open and crank with the fuel shutoff solenoid disconnected then it should pump out.

you should be getting a nice squirt not a little trickle.

i really would replace the lift pump either way, but it is beginning to sounds like that's the issue. :)
 
So after more wasted posts everyone is agreed the op should fit a new lift pump!
You tight #### get your wallet out, or do you need instructions how to do that as well:D:D:D
 
So after more wasted posts everyone is agreed the op should fit a new lift pump!

You tight #### get your wallet out, or do you need instructions how to do that as well:D:D:D


I didnt want to replace a lift pump that is actually showing its working, through the outlet pipe (diesel present) with a replacement that may not last. So they arent wasted posts when it could be another issue ive missed.
 
I didnt want to replace a lift pump that is actually showing its working, through the outlet pipe (diesel present) with a replacement that may not last. So they arent wasted posts when it could be another issue ive missed.


The problem is the lift pump is such a weak point dont believe what you are seeing
Dont forget not only has it got to deliver a certain amount of fuel its got to deliver it at pressure as well, so may be putting fuel through, but either not enough quantity or enough pressure
I got sick of replacing them on my 200 so went all electric.
I have seen it on many types and makes of engines, Ive always wondered why filter isnt before lift pump to save **** messing with the poppet valves.

Ps I habe a selection of crow bars to assist with opening your wallet:D
 
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