300tdi poor power still a problem

[Souster]

Hi all

Some time ago i had a problem with poor performance on my 300tdi before the turbo boosts. And yesterday it came to my attention again that its very down on power at low revs. I had to set off up a steep hill yesterday, approx 20% gradient, and the vehicle would not pull itself up in 1st gear, it kept stalling each time. I had to go into low range, tackle the hill and then back into high range. Surely thats not right? This was without any load in the vehicle.

Since i posted about the problem last ive checked or replaced a few things -

New delphi lift pump

Cleaned and flushed intercooler

Checked turbo/intercooler pipes

Checked boost diaphragm for splits

Replaced diesel leak off pipes

Clean airfilter

New fuel filter 6mths ago on purchase of car

Cambelt replaced by garage on purchase

Valve clearances checked

Once the turbo is spooled up it seems fine, and the top end speed is fine and acceptable, but it seriously lacks low down grunt, what a land rover is known for.

Ive given the FIP a slight tweek, smoke screw on the top 1 and half turns, star wheel half a turn, and diaphragm a quarter turn. But while this helps in every day driving, its not helping the low down grunt and torque as much. Its now smoking a little bit in car headlights since the pump adjust too.

Any help would be greatly appreciated. Thanks again

[IanT90]

I am by no means an expert but could suggest couple of areas to consider. Injectors fuel air mix at low revs might cause more problems than with general running around town. Smoke might also suggest poor mix ? Again not an expert but sure turbo only kicks in at a certain min rev so if you don't reach those revs no turbo anyway ? Final thought is wear in one or more cylinders or damaged/sticking valves you can pick up a cheap compression testing tool see if your firing on all cylinders so to speak. I have a 300tdi and believe me I have no problems with low end torque.

Good luck hope it gives you some other options to think about.

[Souster]

I am by no means an expert but could suggest couple of areas to consider. Injectors fuel air mix at low revs might cause more problems than with general running around town. Smoke might also suggest poor mix ? Again not an expert but sure turbo only kicks in at a certain min rev so if you don't reach those revs no turbo anyway ? Final thought is wear in one or more cylinders or damaged/sticking valves you can pick up a cheap compression testing tool see if your firing on all cylinders so to speak. I have a 300tdi and believe me I have no problems with low end torque.

Good luck hope it gives you some other options to think about.

Thanks for the reply Ian. It never smokes at all really untill i tweaked the fuel pump a little bit. Now it does smoke a bit in car headlights, but thats down to my adjustments on the pump. I'll have a look into compression testing as you advise. I dread it to be a fault deep into the engine, well beyond me

[simonb]

Is throttle cable properly adjusted - with engine off, pedal to floor, is lever wide open against stop on FIP? The cable locknut can wind itself along by engine vibrations and restrict the throttle movement on the FIP.

[Tanuki]

What do you mean by "low-down grunt?" You're saying "before the turbo boosts" - well, sure, it's going to be lethargic before the blower's doing its stuff.

That's why you have a gearlever.

Change down early. Change down often. If in doubt change down.

There's a rev-limiter built in to tell you when you really need a higher gear.

[diggervan]

Had similar problem on a tracktor once long time ago it struggled to pick its revs up once turbo kicked in it was fine.

Checked all usual suspects filters/fop/etc. turnd out to be silencer had collapsed in changed that and it was fine

Not saying this is your problem but something else to look at.

Hope this helps Bob

[Phil Hancock]

I used to drive a Muir Hill tractor powered by a Ford 380 diesel, that went well at high revs but low down was carp, it started fine and ran clean. The engine had been fully rebuilt before purchase and when I had a look at the engine the fuel pump was fully advanced. The timing gears were helical cut so I suspect the workshop monkey had got the timing 1 or 2 teeth out and could not be bothered to pull the pump and move the gear to realign the timing marks on the gears teeth hoping that fully advancing the pump body would bring it close enough.

[Souster]

What do you mean by "low-down grunt?" You're saying "before the turbo boosts" - well, sure, it's going to be lethargic before the blower's doing its stuff.

That's why you have a gearlever.

Change down early. Change down often. If in doubt change down.

There's a rev-limiter built in to tell you when you really need a higher gear.

Theres only so much you can change down though. As i say in my original post, i was in first gear and had to go into low range, just to make it to the top of a hill on a normal road. Yes it was steep, but if a normal car can manage it - a land rover deffo should. I had come to a stand still on he hill, come to pull away and it wasnt having it.

[Souster]

I'll bare in mind the silencer and the timing chaps. Thankyou

[reb78]

Worry is that fiddling with the FIP will mask the problem somewhat. Turning the diaphragm a random 90 degrees might not help at all - you need to know where it is set initially.

It sounds like a more fundamental problem. You've checked a lot of the simple stuff, so timing would probably be whee I would look next. I think others have also suggested compression checks?

My 200tdi 110 trundled up the wrynose pass in Cumbria quite happily in 1st and 2nd hi range with 7 people in it the other day, so there is definitely an issue here. I only used lo range on the hard knott as it meant I could trundle slowly up the pass and enjoy the view, it would have done it in hi.

[Souster]

Worry is that fiddling with the FIP will mask the problem somewhat. Turning the diaphragm a random 90 degrees might not help at all - you need to know where it is set initially.

It sounds like a more fundamental problem. You've checked a lot of the simple stuff, so timing would probably be whee I would look next. I think others have also suggested compression checks?

My 200tdi 110 trundled up the wrynose pass in Cumbria quite happily in 1st and 2nd hi range with 7 people in it the other day, so there is definitely an issue here. I only used lo range on the hard knott as it meant I could trundle slowly up the pass and enjoy the view, it would have done it in hi.

Thankyou reb78. I totally agree.

The timing belt was done by a land rover garage about a 1000 miles ago. Didnt own the land rover long before i had that replaced. Am i right in saying that when the timing belt is changed, the FIP is not timed at the same time? Therefor the timing of the FIP could be out?

Whats the best way of checking the FIP timing?

Failing that i think a compression test is next on the cards.

A friend suggested it could be due to the 285 tyres on it. But i find this hard to beleive

[reb78]

The FIP should be locked to match the engine locked at TDC before the old belt is taken off. If nothing is moved and all is put back correctly, its a case of matching up the timing marks on the crank and cam pulleys and replacing the belt. It is possible to get this a tooth out and mess up the timing (front cover would have to come off to check this).

Worth checking the FIP timing at TDC - should be an inspection plate on the front cover over the FIP pulley. Set the engine to TDC and check a 9.5mm (i think its 9.5) drill bit or the proper timing pin slots easily into the pump.

Best thing is to download the service manuals - take a look in the tech archive for the links. They explain the whole process better than me!

This is where i would start anyway.

[cackshifter]

Well worth checking the camshaft timing as well. I bought my 110 from a well known purveyor of carp in the Midlands who had changed the timing belt, and it ran like a dog I now realise. I had to change the crank oil seal and did the belt at the same time, and realised they had timed the cam a tooth out. Much easier to see if the rad is out. Once timed right it was a different animal.

[Rabat]

I had a similar problem a while back. Struggling to accelerate. The fuel lines were sucking air. In my case it turned out to be an air leak on the sedimentor (fixed with a skim of sealant round the rubber o ring) , but it could possibly be a hole in the tank or a leak anywhere else along the fuel lines.

[Souster]

Hi guys.

Apologies for being a nightmare with land rover faults. But it's all good fun and a learning curve I really enjoy.

Right, I'm digging up this thread. Because my dad has bought a 300tdi defender. With 40k more miles on the clock. The engine is far superior to mine. I'd lived with the lack of power since this thread ans thought it was natural due to not finding the problem.

Well I was very wrong. Every 300tdi I've been in now has far more power than mine. My dads pulls from lower revs in higher gears. Lots of torque as the 300tdi is well known for. The power on mine comes in like a 2 stroke engine. Poor untill it's reved and the turbo is well spooled up (can hear it). Even very small loads in the back are noticeable on the engine. Also, mine is much more noisy. It has like a knocking noise from the top end. I always assumed it was diesel knock. But now It's putting towards internal issues.

Anyway, I decided it was about time I got to the bottom of the problem being as I knew something was definitely not right. So I compression tested the engine and here are the results:

Cylinder 1: 340 psi

Cylinder 2: 390 psi

Cylinder 3: 363 psi

Cylinder 4: 363 psi

I then put a few squirts of oil down the bore of cylinder 1. And a reading came back of 470 psi. Not sure if I used too much oil or not. What do you guys make of these results? Are they showing a fault? I know that adding oil and if the reading is higher it's down to poor rings. But this problem is deeper than that I beleive.

Over the months I've checked things:

-FIP Vacuum pipe from turbo is fine.

-Boost diaphragm fine

-Turbo play is equal to another well powered 300tdi

- all filters new and 15w40 oil used to reduce knock. Unsuccessful

- cambelt replaced due to leaking crank seal (not My work) and I'm 100% certain it's timed correctly.

Can anyone shed any light? I must admit I'm not familiar inside the engine. But would be willing to give it ago.

Thanks alot

[Challo]

Don't want to sound insulting, but have you tried changing the fuel filter?

Mine was well down on power and that sorted it.

Must have been contaminated fuel as it was only installed about 4 months.

[KenM]

Have you had the front cover off to check the timing? You need to check not only with the timing pins in the flywheel and injection pump but also that the cam is in the correct position. You could also loosen the nuts on the top of the injectors one at a time whilst it running and listen to the change in note, if so this could point to problems with the injectors or at least problems with certain cylinders, good luck.

[Souster]

Thanks Challo and KenM. Fuel filter has been replaced twice.

I've also had the front cover off and checked the timing. It's spot on. I had to replace the belt due to crank seal failing after a land rover independent did it.

I haven't tried that with the injectors. I like to sound of that. So is it just slackening off each union one at a time and what should I expect to see or hear?

Many thanks both

[KenM]

Its the equivelent of pulling a plug lead of a petrol engine you should notice a change in the engine if you have a heavy kock it might lessen or disappear or if you hear no or very little change these could point to injector problems ypour really listening to see if you have the same change on each injector.

If you do notice much difference on any injectors try swapping a couple round that way you will know if its rhe injector or a problem with that cylinder.

[Challo]

I have stripped and cleaned my 300tdi injectors in the past.

Used petrol to remove the bulk of the muck.

Then bought a cheap ultrasonic cleaner from aldi or lidl and gave them 20 minutes in that.

Reassembled using diesel as a lubricant.

Maybe worth fitting new nozzles.

Just make sure they are genuine Bosch as i haven't heard good things about the chinese variants.

[Souster]

cheers challo, Could faulty/ poor injectors cause a knocking noise too?

[Souster]

Slackened off each injector this afternoon one after another. Each one gave virtually identical results, made the engine hunt and hesitate. The flow to each injector pipe also seemed identical.

Back to the drawing board haha.

[Nigelw]

You mentioned tyres, 285/?x16?......

What TXB are you running? 1.4? 1.2?

I found that my gearing is horribly high in my Disco with a 1.2 TXB and 235/85x16 tyres!

[Souster]

You mentioned tyres, 285/?x16?......

What TXB are you running? 1.4? 1.2?

I found that my gearing is horribly high in my Disco with a 1.2 TXB and 235/85x16 tyres!

I am running 285/75/16 tyres mate yes.

1.4 defender transfer box too.

Those size tyres should effect it to this extent though should it? And especially not the knocking noise. After hours of research I'm beginning to think it's bad diesel knock.

Cheers

[sixfeetofmud]

I was down on power once and I traced it back to the sender unit not fully sealed at the tank .