HairBear

Member
I've tried searching for the answer on here but I haven't been able to find the answer so please forgive me if I've missed it and for asking again.

last week driving home over the mountain (if you are in the Isle of Man or visit here then you'll know where I mean but it really isn't important) I noticed that the car - Disco 2 td5 - wouldn't hold its speed up the climb and eventually had to go down to second just to keep going. I've checked the wastegate and that seems fine, the turbo sounds like it is working fine but the car feels like it hasn't got one at all anymore. Changed the fuel filter today (along with oil, air and rotor filters just for good measure) skinned knuckles but no joy powerwise.

Any ideas please?

Thanks a million.

Ian
 
First check on a TD5 would be Oil in wiring loom, then turbo air inlet pipe blocked/trapped/holes/de-laminated, intercooler air hoses blocked/holed/de-laminated, then onto fuel lines for chafing, fuel sender unions splitting.

All the above have been covered many times in the forum ... hence why I know of them, mine's a 300 Tdi ... ;)
 
prob not oil in loom as that also causes misfire & non starting-TD5's are gutless anyway to a point...I have changed pretty much everything to improve things, major fuel components, looms, wastegate tweaks, egr removal, intercooler clean, new turbo hoses, MAF...but its still pretty much the same!

Im having mine remapped in the next few months which seems to be the consensus for improving things..
 
I understand that, but if HairBear has previously run the same route and if it's not gutless usually, then summat's wrong, and they are where I'd start .. ;)

No point re-mapping or chipping etc unless the vehicles running properly to start with, IMHO.
 
I understand that, but if HairBear has previously run the same route and if it's not gutless usually, then summat's wrong, and they are where I'd start .. ;)

No point re-mapping or chipping etc unless the vehicles running properly to start with, IMHO.
You are correct that it is a new problem and not just looking to improve on standard. I'll try the hoses etc first and work my way through the list. Deffo no misfire, idles well and smoothly and revs freely when in neutral but an absolute shocker when under load so something has changed/broken.

I'll look into things like removing EGR valve and blanking off etc when I get it back to normal. BTW this is a similar improvement to that that can be made to newish carbed triumph bonneviles and for the same reason - emissions.

Thanks for the replies and keep em coming.
 
Had simular problem with my TD5 completly gutless at low reves had to change down to go up hill. Changed the air flow meter (MAF) for a genuine LR one. BIG difference !! Now pulls well at low revs and holds power up hill. ????
 
You are correct that it is a new problem and not just looking to improve on standard. I'll try the hoses etc first and work my way through the list. Deffo no misfire, idles well and smoothly and revs freely when in neutral but an absolute shocker when under load so something has changed/broken.

I'll look into things like removing EGR valve and blanking off etc when I get it back to normal. BTW this is a similar improvement to that that can be made to newish carbed triumph bonneviles and for the same reason - emissions.

Thanks for the replies and keep em coming.

I removed the egr valve, fitted blanking kit, put a de-catted exhaust pipe on, along with a straight through middle exhaust section, when i bought my TD5. BIG improvement:D. As said before whilst youve got it in bits, clean the sensor in the inlet manifold.

Hope this helps
 
my money's on the MAF.:)


YEP, I agree that's a good start point.

If he had a turbo boost gauge fitted (about £15, easy fit) he would spot immediately he put his foot down that the BOOST was not hitting the 1 bar range.
No Boost - No OOOMPH.

If the MAF thinks not a lot of air is going in EVEN IF the turbo is blowing hard, the ECU won't fling in much fuel because it never wants to fling in more fuel that there is air to burn it in. The shortage of fuel affects the turbo boost too (less fuel = less boost) and so a dirty or defective MAF can have a huge effect on the whole engine performance.

Well worth a try.

It costs nothing to clean it carefully with meths and a cotton-bud.

CharlesY
 
Thanks guys. I will try most or all of the suggestions when I get my, now knackered Disco home. I had to abandon it in a pub car park tonight half way home. Very little power and decreasing as I drove along. It was dark but I'm pretty sure that there was some smoke too. Also a slight knocking sound as if at least one cylinder had given up the ghost or a nasty misfire. Fortunately a pal at work has a big pickup and will tow me home tomorrow night, then I'll have to revert to a motorbike until Christmas break then get to work on the car.

Any more ideas very welcome and if you are interested I'll keep you posted.

Cheers

HB
 
Thanks guys. I will try most or all of the suggestions when I get my, now knackered Disco home. I had to abandon it in a pub car park tonight half way home. Very little power and decreasing as I drove along. It was dark but I'm pretty sure that there was some smoke too. Also a slight knocking sound as if at least one cylinder had given up the ghost or a nasty misfire. Fortunately a pal at work has a big pickup and will tow me home tomorrow night, then I'll have to revert to a motorbike until Christmas break then get to work on the car.

Any more ideas very welcome and if you are interested I'll keep you posted.

Cheers

HB

Last week my TD5 did much the same and it was the in-tank fuel pump that had failed.

I got a new one, and the car sprang back to life.

BUT .... there are TWO MESH SCREENS in the pump. which do clog up, and can cause EXACTLY the symptoms you report.

The screens in mine were blocked solid, and so my old pump may be OK now I have cleaned it out. Get the pump out and check the recent threads from MASTERMAC and you might just save yourself a lot of cash.

The pumps are easy to strip down to get at the mesh screens, but you will need to be careful of some of the little tags that hold it together.


CharlesY
 
Finally got to the fuel pump, mesh screens and a new fuel filter. All ok. So still no progress. Just moved the car onto the drive again and mountains of black smoke when attempting to rev and won't rev beyond about 3k then drops off again.

Any more views? Is this still possibly something to do with the MAF?

Cheers again

Ian
 
sound like the maf. unplug it and see if it's any better (ECU will use default values and not the duff ones the MAF is sending)
 
sound like the maf. unplug it and see if it's any better (ECU will use default values and not the duff ones the MAF is sending)
Tried it - no difference. Have now also got to the red plug on the ecu and found tons of oil. Tried a clean with rag etc, no cleaner to hand or any other car to use to go and get some, and again no joy. Mate, who is a mechanic, has just had a look and cannot come up with any bright ideas except that the EGR valve seems to be ok, well not siezed anyway, and teh turbo is fine. gonna try to get a new MAF and try fitting that and get some contact cleaner to clean the ECU.

Something will work and I don't want to spend £60/hr for some one else to work through what I already have done.

BTW no warning lights with the MAF unplugged.

Ian
 
The oil in the ecu isn't good but this would normally give white smoke. The injector harness certainly needs replacing but I don't think it's likely that it's the cause of your current problem.

black smoke is usually overfuelling. This could be due to a split or delaminated turbo hose, turbo hose come off, blocked air filter or fooked egr valve.
 
Finally got to the fuel pump, mesh screens and a new fuel filter. All ok. So still no progress. Just moved the car onto the drive again and mountains of black smoke when attempting to rev and won't rev beyond about 3k then drops off again.

Any more views? Is this still possibly something to do with the MAF?

Cheers again

Ian


I think you have one or more failed lower copper washer on an injector.

This does two bad things:

1. It allows fuel in the gallery in the cylinder head to drop DOWN into a cylinder, causing masses of smoke when you start up.

2. GAS from the cylinder leaks UP into the fuel gallery causing big time loss of power and misfiring, even up to stopping the engine.

Change all 5 copper washers and all 5 O-rings.

It's not a sore job - but do it EXTREMELY CAREFULLY.

CharlesY
 
Right. It's not the fuel pump or filters. It's not the MAF, new one on and no difference, look out on ebay; it's not the EGR valve - blanking kit on. ECU red connector cleaned as best I can. Turbo spinning and feels smooth. Guess I'll check the turbo hoses next then completely stuck unless I look at the injector washers but scared stiff of tackling those.

Any other ideas very welcome.

Cheers


HB
 
prob not oil in loom as that also causes misfire & non starting-TD5's are gutless anyway to a point...I have changed pretty much everything to improve things, major fuel components, looms, wastegate tweaks, egr removal, intercooler clean, new turbo hoses, MAF...but its still pretty much the same!

Im having mine remapped in the next few months which seems to be the consensus for improving things..


keep us updated with re-map foss., i,m in the arly stages of trying to improve mine slowly, just give it a service, checked wastegate arm- seems free, gonna change wastegate solenoid next, also i,ve gon back to paper filter, did hav a K n N in there but it was in a right state caked in a layer of wet dusty grime, tried cleaning but made it worse i fink?:doh: so paper all way now, wen dirty , bin em, ecu was dripping in oil so cleaned out , will do again in few weeks to check, wll clean out intercooler next along with egr blank,
 
I think you have one or more failed lower copper washer on an injector.

This does two bad things:

1. It allows fuel in the gallery in the cylinder head to drop DOWN into a cylinder, causing masses of smoke when you start up.

2. GAS from the cylinder leaks UP into the fuel gallery causing big time loss of power and misfiring, even up to stopping the engine.

Change all 5 copper washers and all 5 O-rings.

It's not a sore job - but do it EXTREMELY CAREFULLY.

CharlesY

Not doubting you, am very apprehensive about trying this, but could you explain why the copper washers would fail when they have not been moved since the car was built.

BTW the smoke is less since cleaning the ecu connector (not hugely but noticeably)power seems very marginally better (could be wishful thinking) but won't rev past about 2250 under load and takes an age to get there. Will eventually get up to speed, well 30mph and probably higher but only if I select a higher than usual gear and accelerate on torque. Someone has suggested maybe a blockage in the exhaust, perhaps the cat. Does anyone have any thoughts on this?

As always thanks.

HB
 

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