TD5 sticking at 3,000 rpm

[surfingooner]

HELP !!! - I have been endlessly researching this forum and other forums as to how to solve my TD5 never revving past 3,000 rpm. Does anyone know of a fix that solved it, I have read lot's of potential culprits it could be, and have been trying to work out what my problem is on another thread, but I can never see where someone cured it ?


There are a number of people who have experienced the same problem, so there must be (I am hoping) a common issue that was eventually found ?


I have changed the MAF, boost modulator, fuel filter, air filter, newish fuel pump, cleaned the ECU, checked fuse F2, cleaned the MAP, replaced hoses to the modulator to the wastegate.


I am sure it is ECU related and not a fuel blockage, something somewhere is giving bad feedback


I drove a D2 same year over the weekend, his had been chipped with 370k, mine re-mapped with 270k, performance very similar for both, but his would rev freely past 3,000 up to 3,750, mine basically stops at 2,750 and you have to try very hard to get just past 3,000.


And when it does change up it shoots off. It is making such a difference to driving as the engine needs to get past 3,000 to get the momentum to change gear.


Only thing I haven't done to date is change the gauze in the fuel regulator (mainly because it looks pretty tricky) but before I do it, I thought someone out there must have done something when they had the same problem that solved it.


3 years I have had this problem, and am determined to solve it, if I give the car to a specialist it might cost a great deal to find it, if there is a saviour out there..........Any help would be great.

[sierrafery]

Hi, better find somebody with nanocom, record a live "inputs fuelling" log from a longer drive and post it here... otherwise it can be a guessing game cos only cleaning the MAP doesnt fix it if it reads low due to wear and the AAP reading is important too... aren't the turbo hoses delaminated?, is it 15P engine?

[Tank]

Does your TD5 have a "fly by wire" throttle or a cable, should check to see if you are getting full throttle when pedal flat to the floor, good luck, Regards Frank.

[Pierre]

TD5 engines are fly by wire, with throttle pot on the pedal assembly.

Pete

[Tank]

TD5 engines are fly by wire, with throttle pot on the pedal assembly.

Pete
Would start there then, Regards Frank.

[surfingooner]

Hi, better find somebody with nanocom, record a live "inputs fuelling" log from a longer drive and post it here... otherwise it can be a guessing game cos only cleaning the MAP doesnt fix it if it reads low due to wear and the AAP reading is important too... aren't the turbo hoses delaminated?, is it 15P engine?

Think you are right and will search out a friendly nanocom owner in North Melbourne area. Sure it is not a throttle issue, but still have no idea why she won't rev properly.

[surfingooner]

Accessed nanocom at weekend (thank you Railey), whilst we were not able to live-test, I can report as follows:


Car initially logged a driver demand fault 1.5, not sure what that is, no other faults.


Revved to 4,000 rpm no problem, at idle MAF was circa 45, when revving circa 380 - low


Swapped cars over and Railey was 50 - 60 at idle, hit 600 when revving.


So went back to mine, gave it more welly and hit 500, so nearly there. Went for a drive and no difference, struggled at 2,750 up a hill and just did not want to go past 3,100 rpm.


On return it showed overboost fault, I have only 3 turns showing on boost screw, so now backed off to 8 and yes the car is happier at higher revs, but problem still there.


Did digging last night a two points I want to raise reading older posts.


1) Is there the possibility it could be a clutch issue, the previous owner bought the Disco to pull a boat, a very big boat, and was going to by a 4.2 Cruiser after as needed more grunt. The clutch could be slipping ? (Auto)


2) There is a lead that goes behind the rear heat cover, over the gearbox which got pretty fried (lead is black) from old days when the manifold leaked, could I have some kind of electrical shorting problem. I will take a photo this evening, some posts suggest this can create a problem in the ECU.


Any thoughts are very welcome, I am determined to beat this problem !!!


Thanks,


Matt.

[Pierre]

Probably the lead for the oil pressure switch. Does the oil pressure light come on before you start the engine?

If the dash lamp does not light, then repair the lead so that low oil pressure is sensed. I doubt that it affects the max engine speed, though.

Pete

[surfingooner]

119600

[surfingooner]

Yes the light works, there goes that theory then !

[sierrafery]

Ask somebody to rev it above 3000rpm and watch the wastegate rod, it should move a bit even stationary... if it's not moving there's the problem, wastegate modulator or split pressure hose on that path between the intercooler - modularor - wastegate actuator valve or even the valve can be shot.

[surfingooner]

So I wound boost back another 3 turns this evening and had to do run to airport. Boost gauge now down to max 16 when was getting past 20.

Point to make which may identify more is that I floored it from lights entering ring road, in 3rd, stuck at 3,000 but it feels like it wants to do more, wait about 5 more seconds, changes to 4th, shoots along gaining speed for about 3 seconds, then changes back to 3rd again, then another 3 seconds, ease off slightly, back to 4th and off we go for good.

Does this help at all. It has been doing this throughout the problem regardless of where the boost was set at ?

[sierrafery]

the MAP reading would be interesting though...or do you have a boost box fitted?

[surfingooner]

No boost box, I wound the boost back some more and she is going really sweet, best in a couple of years, the problem is there still, but running so much better and no overboost at all. I have played around with 1 x turns, up and down and have pretty much found the best spot. Sure the wastegate is working, I also cleaned the AAP sensor that goes into the air filter.

So so think I will have to now get a live test done on the nanocom to see if can find out more, wish I knew a handy expert who knows Disco's backwards (anywhere in Melbourne) and would be happy to take to them to have a drive and see what they think. Also filled up lat night and will be very interested to see if the economy has improved, car seems so much happier picking up speed now is effortless, but still sticking at 3,000 then hits 4th and whosh.

one last thing I have noticed is when going up a hill, it will change up and a great surge of torque, but as soon as I hit the top and hill levels off she will change down again, high revs and the car seems confused as to what gear she wants to be in. I ease off, then accelerate again and will change into 4th. It's almost if there is a sensor that detects gradient that is messing things up ?

[Jazzman]

I think there is a good chance the intercooler hoses are sucking in or are delaminating. There is bloke in the D2 section who wants one hose out of a kit, which is the opposite hoses to what you need. Perhaps between the 2 of you a deal could be struck to replace the hoses with silicon aftermarket hoses. Does it blow any smoke out the back at 3,000 RPM? If so it would support my theory.

TD5 Air Filter Box to Turbocharger Inlet Pipe (https://www.aulro.com/afvb/discovery-2-a/246252-td5-air-filter-box-turbocharger-inlet-pipe.html)

[surfingooner]

Thanks Jazzman, what exactly does this mean, do the pipes collapse under pressure?

Apologies for the delay, I have been overseas past couple of weeks ?

[loanrangie]

Thanks Jazzman, what exactly does this mean, do the pipes collapse under pressure?

Apologies for the delay, I have been overseas past couple of weeks ?

Correct, effectively choking the engine.

[surfingooner]

Correct, effectively choking the engine.

I have now replaced all the turbo / intercooler hoses with silicon ones, sadly still no change, when I bought them, they suggested the injector seals or the injector wiring loom. They also suggested I book it in to the local Bosch specialist next door to try and find the fault. I have spent so much time trying to get to the bottom of this but bugger me what could it be.....

generally the car is running well, have the boost set right and going quicker than ever, but still all goes to pot when I get to the inclines.

[sierrafery]

A thing to be ruled out is to make sure that all the injector codes are well saved in the ECU memory, a classic symptom of not coded injectors is that the engine can't rev above 3000 so if you take off the cover write down the codes then use tester and compare with what's saved in the ECU maybe the previous owner messed up things there or even if an injector is refurb'd it must come with a new code which has to be saved in the ECU... this is stated in the book too but i've tryed myself when i fitted other ECU and it didnt rev above 2800rpm before i saved the codes, otherwise it ran well.... taking into account all you've already done IMO better rule this out too

[surfingooner]

A thing to be ruled out is to make sure that all the injector codes are well saved in the ECU memory, a classic symptom of not coded injectors is that the engine can't rev above 3000 so if you take off the cover write down the codes then use tester and compare with what's saved in the ECU maybe the previous owner messed up things there or even if an injector is refurb'd it must come with a new code which has to be saved in the ECU... this is stated in the book too but i've tryed myself when i fitted other ECU and it didnt rev above 2800rpm before i saved the codes, otherwise it ran well.... taking into account all you've already done IMO better rule this out too

Thank you, would the re-map from Jose have influenced this ? I say this because it was doing same since I got the car, ie pre re-map. Also would the codes be a problem as the car revs happily over 3,000 in neutral ?

[surfingooner]

Also been reading Jimbob's post and symptoms seen to be very similar, albeit minus a trailer. When I put it on the nanocom for test in neutral, mine seemed to have to work harder to get the same readings for the MAF than the TD5 the nanocom came from, mine read lower at idle also. I have replaced the MAF, but was second hand, I was told it had been tested and was working properly, and so to date have been loathed to pay out for another new one without being sure of the change. I also swapped over MAF's with another member and didn't cure the problem, but I keep coming back to it, it plays on my mind !!!

Will be interested to see what Jimbob says on Monday.

And Sierraferry, re an earlier post that got lost when there were issues with the website, my boost gauge is tapped in between the modulator and the wastegate, so I have to move this to pre-modulator right ?

[sierrafery]

Thank you, would the re-map from Jose have influenced this ? I say this because it was doing same since I got the car, ie pre re-map. Also would the codes be a problem as the car revs happily over 3,000 in neutral ?In this case i dont think it's about injector codes though won't hurt to check if you'll ever take off the cover anyway, also the remap shouldn't affect them.... the fuel pressure becomes next suspect, did you ever check the strainer which is under the FPR in the head?


And Sierraferry, re an earlier post that got lost when there were issues with the website, my boost gauge is tapped in between the modulator and the wastegate, so I have to move this to pre-modulator right ?
Yes

[surfingooner]

In this case i dont think it's about injector codes though won't hurt to check if you'll ever take off the cover anyway, also the remap shouldn't affect them.... the fuel pressure becomes next suspect, did you ever check the strainer which is under the FPR in the head?


Yes

thanks for this, ok the strainer will be next, do I need to buy any replacement gaskets to do this ?

[sierrafery]

thanks for this, ok the strainer will be next, do I need to buy any replacement gaskets to do this ?
Yes a FPR gasket

[surfingooner]

A couple of weeks have passed and have been pondering yet more, and I keep coming back to the torque converter. Having replaced pretty much everything, and have also been driving a fair bit using the box, and when locked up in 3rd, she flies along, get to 85 and change to 4th and that lovely steam of torque keeps coming.

the guy who owned my LR before me had a very big boat, basically the biggest I have ever seen being towed, he was selling the LR to get a 4.2 Landcruiser.

All still ill work in progress, but if I use a reasonable amount of go from standstill, I will get to 85 without any lock up (90% of driving) Foot down hard and still no lock up till 80, the car will struggle in 3rd at about the 2,750 with very little change in speed, but if I do same in 3rd the standstill to 100 is very different. If I accelerate right and get the lock up in 3rd then she flies. Any hills really exaggerates the problem, all revs and no speed gain.

so reading other posts, at this point I am meant to do a stall test, but will this truly diagnose the problem if the car is 'slipping' when in the higher rev range ? Any further thoughts gratefully received.

[loanrangie]

Might be worth a call to the ZF specialist in Thomastown and then take them for a spin and see what they think.

[surfingooner]

Might be worth a call to the ZF specialist in Thomastown and then take them for a spin and see what they think.

Thanks, gave a company a call and receptionist recommends I get it on a diagnosis machine and then they take it for a spin. $100. I did a stall test today and came out at 2,800 which I think is ok, so not sure what to do next. Been doing all driving playing around in 3rd and 4th, sometimes on flat I get well past 80 in 3rd and still the converter does not lock-up. But once it does she goes so well. Very annoying !!

[Tins]

I'd be following up the auto thing. Mine did this intermittently before the auto failed. Engine seemed to be straining to rev harder but couldn't. Revved fine in neutral.

[surfingooner]

Had a chat with TCT and they can do the equivalent of the Ashcroft for around the $1,000 mark. I have given a number by them for a transmission specialist in Ringwood they recommend to get the current one out and re-fit, they recommend I get the auto serviced at the same time as have 280kms on the clock. So making the call for that tomorrow.

Have to start saving now but at this point think When I'm finally ready do it I will go with the Ashcroft as that comes out at $550 and too good a saving to pass by.

Back to to the point and sure it is something to do with the clutch in the converter that is the problem. The boat it used to pull was huge.

[Tins]

Had a chat with TCT and they can do the equivalent of the Ashcroft for around the $1,000 mark. I have given a number by them for a transmission specialist in Ringwood they recommend to get the current one out and re-fit, they recommend I get the auto serviced at the same time as have 280kms on the clock. So making the call for that tomorrow.

Have to start saving now but at this point think When I'm finally ready do it I will go with the Ashcroft as that comes out at $550 and too good a saving to pass by.

Back to to the point and sure it is something to do with the clutch in the converter that is the problem. The boat it used to pull was huge.

They have a history.. They were seriously underprepared for what the Aus and US market would expect of them. They really need a good cooler if they are towing. The oil capacity is way too low for such hard work. For example, I have a mate who has a 79 Series Toyota, chipped and modded to the max ( Featured on the cover of 4X4 mag 123163 ) which has the auto out of a Silverado in it. Torque and power like you would not believe. His boat is massive as well. So is his trans cooler.

[surfingooner]

They have a history.. They were seriously underprepared for what the Aus and US market would expect of them. They really need a good cooler if they are towing. The oil capacity is way too low for such hard work. For example, I have a mate who has a 79 Series Toyota, chipped and modded to the max ( Featured on the cover of 4X4 mag 123163 ) which has the auto out of a Silverado in it. Torque and power like you would not believe. His boat is massive as well. So is his trans cooler.

Thanks for that, so in my ignorance and wanting to learn a bit more, so what is happens to the transmission when this is happening. What parts 'fail' or become weaker as a result ?

[Tins]

Thanks for that, so in my ignorance and wanting to learn a bit more, so what is happens to the transmission when this is happening. What parts 'fail' or become weaker as a result ?

I'll let the gurus answer that one.

I have posted this pic a few times to show how well my car towed. I towed that car about 1,000 km, on a hot day. The car towed it beautifully. Now, the car had around 260,000 km on it. It was serviced regularly. It wasn't too long after this that the car started to have some issues. The M + S flashing, limp home mode. If I stopped and restarted it would clear, but it got worse. So, I got the oil changed. It was black, and it stank. It had been changed about 20,000 km previously and was a good colour then ( I'd expect some discolouration, which was there ). The oil change didn't help, and a couple of months later the trans failed completely. No drive at all forward, still had reverse. The oil was black again.
I haven't done a lot with autos, as they scare the bejesus out of me, but to me black equals burnt, and the only things I can think of that would burn in the auto are the clutch packs or the oil itself. Both things suggest excessive temps.
To dry fill the auto takes around 9 litres of oil. That may seem a lot, but I don't think it's enough. If I ever get my car back ( don't ask ), I want to fit a much bigger cooler, first for the obvious airflow reason, but second for the increased capacity.
I am no expert, and don't claim to be, but I think my experience shows what I meant by saying the cars were underprepared for what we would ask of them.
Having said that, I like my Disco, and would prefer to upgrade it rather than replace it, and am following the various threads on here about transmissions.

123199

[Tins]

123199

That pic also reminds me, I want to reinstate the SLS.

[surfingooner]

TCT recommended a specialist gearbox company not too far from me, and the just quoted $1,200 to service the gearbox and change the TC over for the Ashcroft unit - Ouch !! But they do use good oil so they told me.

So looking like the whole project is going to cost $1,750 plus the postage to get an Ashcroft TC out here. Looks sadly like a back-burner thing, $1,200 wow, someone here said should be done for about $580.....

Phone around time I guess....

[Vern]

I'd keep saving and get a whole transmission sent over!

[Sitec]

Did you note and check those injector codes? Worth doing before you spend on a box.. They're all readable with the rocker cover off....