Low power...

Hi Guys and Gals
My 300tdi defender went gutless on me.... Seemed decent through the low gears and flat cruising but show it even a mild hill and it's down through the gears.... Pulled things down and lots of oil in the intake side (turbo seals failed).... Bought a boost gauge and only about 4psi maxed..... Went through the lot, pipework, intercooler, air filter, no leaks or obstructions (and no black smoke).... Moved on to fueling, changed filter, checked lift pump pushing fuel out of bleed on filter nicely, opened the top of the pump and the fueling pin seems to pop out nicely, diaphragm sound and blew down the actuating pipe from the turbo end and no sign of leakage.... Exhaust seems to be blowing through nicely and not obstructed.... Changed turbo and just the same.... No boost and couldn't pull its trousers up!!..... Went through the lot again (most of it more than once).... Running through my store of head-scratching and thought I'd try here before admitting miserable defeat and taking it to a garage (never like doing that!!)
Any thoughts or things I've missed...... Have thought that my Web purchased boost gauge may be duff, but the lack of pull is real enough.... Also the lack of black smoke is odd for a poor intake pressure (however caused).... Don't know enough about turbos to know if poor fueling/power would perhaps lead to low exhaust flow and therefore low boost..... Starts and runs under light load just fine.

Any thoughts gratefully received

Cheers

Keith

PS... all new silicone hoses and clips... Egr valve removed and blanked.... Giving the hose a squeeze and revving it there's a hardly detectable stiffening of the hose... Should be much more I think... Would tend to confirm the gauge.

K

Defenderer said:

PS... all new silicone hoses and clips... Egr valve removed and blanked.... Giving the hose a squeeze and revving it there's a hardly detectable stiffening of the hose... Should be much more I think... Would tend to confirm the gauge.

K

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Yes, the turbo's boost is dependent on amount of fuel through the engine. So, the induction pipes from the turbo and out of intercooler should firm up when revving the engine from under the bonnet. However, that's nothing compared to say, pulling hard up a hill. The engine revs may be the same in both scenarios, but to get to those revs when pulling up a hill takes a hell of a lot more fuel/air, so the amount of gas going through the exhaust is a hell of a lot more than getting the same revs with no load. So, the turbo would be boosting a lot more.
Is the boost pipe from the turbo to the FIP ok?

Thanks for the reply..... As far as I can tell the turbo/fip pipe is sound (as is the diaphragm under close inspection) ..... Have blown down the turbo end and it holds air til I go red in the face with no feel of it leaking away.
Not at clue it it's viable, but thought of taking the top off the fip and manually depressing the diaphragm with my thumb as I rev it from under the bonnet... Obviously the fueling wouldn't accurately track the boost but it may give me an idea if more fuel under boost is the issue. I could then investigate the feed from the turbo deeper
Thoughts??
K

Defenderer said:

Thanks for the reply..... As far as I can tell the turbo/fip pipe is sound (as is the diaphragm under close inspection) ..... Have blown down the turbo end and it holds air til I go red in the face with no feel of it leaking away.
Not at clue it it's viable, but thought of taking the top off the fip and manually depressing the diaphragm with my thumb as I rev it from under the bonnet... Obviously the fueling wouldn't accurately track the boost but it may give me an idea if more fuel under boost is the issue. I could then investigate the feed from the turbo deeper
Thoughts??
K

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Oops, sorry. Just re-read your first post and you mention blowing down the actuator pipe
Hmmm, not sure if the FIP will function properly with the top off.
Have you done a compression test?
Did you buy a new turbo or recon one?

The turbo is new but not oem.... Hard to think the old turbo (albeit with leaky seals) and new one both faulty the same way.
My plan is to take the top off the fip... Rev it to about half revs then gently push the diaphragm down with my thumb thereby increasing the fueling to see if it has any effect on the boost.... Plenty of owners have driven round with leaky pipes with no lasting damage so running for a few seconds with the top off shouldn't be an issue... Pressing too far will just overfuel giving me smoke but hardly likely to do any damage for a few seconds either... Well that's my logic anyway for what it's worth.
Thanks for your help with this
K

Sounds like it's worth a go.
When I rebuilt my engine a few years back, the first turbo I put on didn't boost very well. I sent it back and they replaced it. The replacement boosts better, but I think is passing too much oil. Both Garrett turbos, but recon ones.

Curiouser and curiouser..... Motor starts and runs with the top off the fip.... Rev to half and push down on the diaphragm and no effect at all..... Would expect black smoke (none... Not even at idle)..... Took out the diaphragm and even with the pin fully out not a sniff of smoke or change of boost..... Looks like it's possible fueling is being restricted elsewhere (or I've missed something completely obvious.... Not something I'd bet against )
New fuel filter, only done few miles testing up the road.... If I open the filter bleed at idle fuel flows out plentifully so it looks like the lift pump is working..... Probs with injector pump (or timing) or injectors maybe...... Engine idles and runs sweet not under load.
Open to any ideas.
Thanks
K

Defenderer said:

Curiouser and curiouser..... Motor starts and runs with the top off the fip.... Rev to half and push down on the diaphragm and no effect at all..... Would expect black smoke (none... Not even at idle)..... Took out the diaphragm and even with the pin fully out not a sniff of smoke or change of boost..... Looks like it's possible fueling is being restricted elsewhere (or I've missed something completely obvious.... Not something I'd bet against )
New fuel filter, only done few miles testing up the road.... If I open the filter bleed at idle fuel flows out plentifully so it looks like the lift pump is working..... Probs with injector pump (or timing) or injectors maybe...... Engine idles and runs sweet not under load.
Open to any ideas.
Thanks
K

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When it’s struggling, will it struggle to the point it stalls? Have you tested for air in the fuel system?

Hi Mick

Nope... Never stalls.. Symptom on the road is... Pulls fine in lower gears but on anything resembling a hill in higher gears loses speed and needs a change down.... Like a N/A engine by the feel of it..... Runs sweet enough just totally gutless compared to past performance.... Putting gauge on it there's only a few psi of boost but inlet integrity checks out and same with new turbo fitted ... Leaning towards a fueling issue.
Cheers
K

Blocked injectors?

Defenderer said:

Curiouser and curiouser..... Motor starts and runs with the top off the fip.... Rev to half and push down on the diaphragm and no effect at all..... Would expect black smoke (none... Not even at idle)..... Took out the diaphragm and even with the pin fully out not a sniff of smoke or change of boost..... Looks like it's possible fueling is being restricted elsewhere (or I've missed something completely obvious.... Not something I'd bet against )
New fuel filter, only done few miles testing up the road.... If I open the filter bleed at idle fuel flows out plentifully so it looks like the lift pump is working..... Probs with injector pump (or timing) or injectors maybe...... Engine idles and runs sweet not under load.
Open to any ideas.
Thanks
K

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Did you reference the diaphragm before you took it out?
I don't know what the max travel on the needle is, but not too far I wouldn't have thought.
Looks like the FIP needs checking out.

Yep..... Not messed with..... And punch mark facing block gives a baseline refit if you don't.... Thinking myself that the injector pump and the injectors are the one link I haven't checked...... I intend to take it in for a cam belt so will do that sooner rather than later and get someone more familiar than me to mess with those while it's in.
Just seems odd that the fip diaphragm had no effect on fueling (if smoke is anything to go by) no matter how far the pin moved.... Would have expected something at idle at least.
Cheers
K

Defenderer said:

Yep..... Not messed with..... And punch mark facing block gives a baseline refit if you don't.... Thinking myself that the injector pump and the injectors are the one link I haven't checked...... I intend to take it in for a cam belt so will do that sooner rather than later and get someone more familiar than me to mess with those while it's in.
Just seems odd that the fip diaphragm had no effect on fueling (if smoke is anything to go by) no matter how far the pin moved.... Would have expected something at idle at least.
Cheers
K

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Maybe the lift pump is not as fit as you thought. It might be pushing some fuel out of the bleed valve on the filter, but when it's got to overcome the resistance of the filter it can't do it.

Al2O3 said:

Maybe the lift pump is not as fit as you thought. It might be pushing some fuel out of the bleed valve on the filter, but when it's got to overcome the resistance of the filter it can't do it.

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They're not expensive and easy to swap out.

That's something to follow up (I like cheap and easy! .)..... Pretty decent flow out of the bleed screw but that doesn't tell you if it has pressure behind it (I have a fuel pressure gauge kit.... If the scale is not too blunt and I have the right fitting I can get a reading off that tomorrow (guess it will be pretty low even when right and not the sort of info you find in the manual.. But worth a look!)

Thanks

K

Defenderer said:

That's something to follow up (I like cheap and easy! .)..... Pretty decent flow out of the bleed screw but that doesn't tell you if it has pressure behind it (I have a fuel pressure gauge kit.... If the scale is not too blunt and I have the right fitting I can get a reading off that tomorrow (guess it will be pretty low even when right and not the sort of info you find in the manual.. But worth a look!)

Thanks

K

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I've no idea what it's supposed to be from the lift pump

I doubt anyone has.... Not your normal spec sheet entry

The pump is pretty much the same as feeds the float bowls on old carb cars... Used to run mine at 3.5 psi.. So if it hits around that then fair enough..... Think it's more about flowing sufficient fuel up to the filter for the fip to suck up and deal with

Cheers

K

It sounds very much like you are having an inconsistent fuel flow. Are your injectors set correctly?

landyfox.... Certainly one possibility is that the injectors are unable to flow sufficient fuel under load.... Will check the lift pump as that can be done myself... Then unless I have a blaze of inspiration I'll be putting it into my local independent landy garage to get them to check and rectify the injectors and pump if needed (will be going in there anyway for a routine cambelt change).... Would just like to exhaust the stuff I can do myself before I start paying their labour rates!!