Any ideas before I just give the car to Landrover to diagnose?

2001 TD5 S stock, only done 36000 miles. Car is immaculate, FLSH etc, drives beautifully, but;

I've noticed a juddering (perhaps a misfire?) when the engine is under heavy load (for example accelerating in third gear at about 2500 revs). If you reduce the load on the engine (ie change up to fourth) the juddering stops.
Also in 5th and doing about 3000 revs, you get no further response from the acclelerator. If you start going uphill, for example, the speed starts to fall away even if you're standing on the pedal.

I'm thinking that something is stuck (turbo?) or just dirty (injector/s). The car has hardly been used the last four years and I think has been standing idle pretty much all of last year. Any ideas? Cheers.

The car could maybe be overboosting. I think when this happens the ECU cuts fuel. It might be that the wastegate arm on the turbo has siezed. To free this you need to remove the rod that operates it and move it back and forth after adding some lube to the moving part.

You're doing the right thing asking here before going to the stealer as it should be something easy to sort. Someone with diagnostics could maybe help you out as well.

Cheers, Andy

andymach23 said:

The car could maybe be overboosting. I think when this happens the ECU cuts fuel. It might be that the wastegate arm on the turbo has siezed. To free this you need to remove the rod that operates it and move it back and forth after adding some lube to the moving part.

You're doing the right thing asking here before going to the stealer as it should be something easy to sort. Someone with diagnostics could maybe help you out as well.

Cheers, Andy

Click to expand...

Just so!

I have fitted a cheap turbo boost gauge to my TD5 Disco just for this reason. It just exceeds 1 BAR / 15 psi boost on a footful of throttle if the revs are 2,000 and up.


If the TD5 has an overboost event the fuel injection is drastically reduced so that the engine doesn't blow itself up. A BIG reduction in power is the result.

If the air filter is really choked that will reduce the mass of air passing the air mass meter, and the amount of fuel injected will be reduced to suit the reduced amount of air getting through. A quick test for this is to whip out the air filter element, clean the crap out of the air box, and go for a run. There is no "mixture" in diesels - just fuel injected into fresh compressed air.

Remember, to move the turbo waste gate rod may require a push of over 40 pounds. Be careful when you do it, but that rod MUST move.

Another way to do it is to jig up an adapter and use an air line. At about 15 - 20 psi the rod should be visibly extended from the capsule.

Take care! Do NOT apply too much pressure or you may rupture the diaphragm in the capsule.

CharlesY

Thanks for the responses. Haynes manual ordered! Overboost diagnosis sounds exactly right. It's not going to be something major, given the car's history (fingers crossed!). It's going to be something that has stuck or is binding from lack of use. And it occurs only when you're asking a lot of grunt, so intermittent lack of turbo sounds right. Will play around. No idea what a turbo wastegate rod even looks like, but I'll get a hammer and chisel out of grandaddy's toolbox and start belting things. Will that work?

corky said:

Thanks for the responses. Haynes manual ordered! Overboost diagnosis sounds exactly right. It's not going to be something major, given the car's history (fingers crossed!). It's going to be something that has stuck or is binding from lack of use. And it occurs only when you're asking a lot of grunt, so intermittent lack of turbo sounds right. Will play around. No idea what a turbo wastegate rod even looks like, but I'll get a hammer and chisel out of grandaddy's toolbox and start belting things. Will that work?

Click to expand...

It might, if you use a big enough hammer on the right bits.

The turbo waste-gate capsule is easy to get at.

Near the top back left of the engine.

CharlesY

see pic that might be attached.

the system for adding pics was thought out by a person with a warped mind.

CharlesY

A new wastegate valve is only £15, I see. Would fitting a new one solve a seized wastegate rod problem, or is that another part?

corky said:

A new wastegate valve is only £15, I see. Would fitting a new one solve a seized wastegate rod problem, or is that another part?

Click to expand...

You won't need it.

Identify three parts ...

the CAPSULE that causes the thrust on
the PUSHROD, that moves
the WASTEGATE LEVER

DO NOT ADJUST THE PUSHROD in a TD5 Disco!!!

What you want to do is clamp a Mole-Wrench on the shaft of the pushrod, and push the rod BACKWARDS. It will take a fair shove to make it move, about 30 or 40 pounds of force I guess. Make sure you don't buckle the rod!

The point is this - The PUSHROD MUST MOVE FREELY BACKWARDS, and spring forwards again when you take the pressure off. The rod MUST be able to move about 20 - 30 mm to and fro.

That is your mission. Make that rod MOVE, and they DO get stuck.

Try NOT to spray WD40 on it, because that will make a heap of smelly smoke and might start a fire.

CharlesY

Will the engine rev out fully under zero load? If not, get the fuel pressure tested. This can be done quite easily by tapping into the fuel pressure regulator block inlet fitting. Pressure should be 4 bar with engine running. Anything less 3.5 bar can give the problems you are experiencing.

My 2001 TD5 had exactly the same symptoms.....a new fuel pump fixed it.

Jerry

Jerrysdisco said:

Will the engine rev out fully under zero load? If not, get the fuel pressure tested. This can be done quite easily by tapping into the fuel pressure regulator block inlet fitting. Pressure should be 4 bar with engine running. Anything less 3.5 bar can give the problems you are experiencing.

My 2001 TD5 had exactly the same symptoms.....a new fuel pump fixed it.

Jerry

Click to expand...

FIRST, fit a newe fuel filter.
Buy a dozen from Britpart or somewhere for a fiver each, and carry them all the time. I changed mine at the M6Toll a couple of summers back. Ten minutes to do it.

then see if that has helped.

SECOND

In the fuel pump are some very fine nylon mesh screens, and if you have had dirty fuel, and / or WET fuel, chances are the screens are choked up.

Take the pump out, and AFTER you have read on LZ how to do this, take the pump body apart, and get to the screens - and clean them.

Don't even think about a new pump until you have done BOTH of these things.

CharlesY

Just a quick note of thanks. Did sort out the Disco eventually. It was a sticking wastegate causing it to overboost - a 5 minute fix. If anyone else has those symptoms, especially in a car that's been left standing a good while, I'd suggest trying that first. Cheers.

corky said:

Just a quick note of thanks. Did sort out the Disco eventually. It was a sticking wastegate causing it to overboost - a 5 minute fix. If anyone else has those symptoms, especially in a car that's been left standing a good while, I'd suggest trying that first. Cheers.

Click to expand...

Well done!

What did you do that told you it was stuck?

Mole-wrench shove?

Who fixed it and how?

CharlesY

Don't you just hate it when they ask for advice but don't offer any....

Dhammadad said:

Don't you just hate it when they ask for advice but don't offer any....

Click to expand...

???
"ask for advice but don't offer any?!"
Maybe they don't have any advice to give, or don't feel they are qualified to give it. He did offer us the advice "to try this first"
He DID say it was a sticking wastegate and a 5 minute fix. One assumes he followed the advice on here on how to fix it. Maybe he would just have felt stupid repeating what had already been said.
At least he did get back to us with what the problem was and that he had fixed it, which is a HELL of a lot more than many do.
But if anyone wants to know what he PROBABLY did, here it is.
He took off the wastegate/turbo heat shield, three nuts/bolts the rearmost one can be a real barsteward to get to.
Remove heat shield.
While holding the knurled adjuster nut with pliers or similar, undo lock nut, you may wish to count the number of threads between the locknut and the end of the thread, this should be thirteen and the easiest way to count them is to put a sharp blade at about 45 degrees across the threaded bar at the locknut, then slide it slowly toward the diaphragm/ actuator, counting the clicks.
Then undo it all so you can free the threaded bar. you may have to undo the two nuts securing the bar to the actuator. Don't lose the nuts and lockwashers down into the engine bay!
This removes the pressure on the actuating rod so it can move easily.
Now move it back and forth to see if it is stuck or binding in the turbo housing. If it is eases it gently back and forth to free it while using the minimum of lubricant.
Once free reassemble, remembering to count the threads on the threaded bar.

Now, if OP did something different to this he can tell us, if he is still reading this thread, but to all those who want to know how it is done, there you go, Merry Christmas!

Whoop!

Seasons Greetings!