Idle 'judder' please help!

Hi all

Sorry to start a new thread on this but I thought it best to describe my exact symptoms as I have read conflicting info, plus please forgive my lack of technical knowledge.

I’ve just bought an L322 TD6 and have started experiencing a ‘judder’ when stationary. This only appears to happen once the car is up to temperature, and doesn’t always happen although it is more often than not. When I come to a halt on the foot brake the car ‘judders’ so I have automatically assumed it’s the gearbox. However, I have noticed that if I knock the car into neutral and coast to a stop the same thing happens, and if I put it in park. If I rev in neutral and then let it drop back to idle it gets more lumpy. If I put it in drive or reverse and let it ‘crawl’ the juddering is more pronounced. As soon as I give it any gas, it pulls away smoothly.

There are no issues when driving normally and the gearbox is extremely smooth, no bumps when engaging drive or reverse.

I may be looking at this too simplistically, but if its in neutral or park I would have thought the transmission was disengaged and therefore if it were a gearbox issue the sensation would stop?

I am running some injector cleaner through in case it’s an issue there.

The gearbox oil and filter was changed at 50k and 75k and the car is currently on 95k.

Any input our suggestions would be much appreciated before I go down the route of a gearbox rebuild.

Many thanks,

Tom.

NEVER coast in neutral with an auto box, you may do damage due to lack of oil pressure.
Sounds like the engine is misfiring.

Thanks Datatek, will get out of that habit immediately before I cause a bigger problem.

I was hoping it wasn't the gearbox!

It needs a bush replaced anyway so I will get it in the garage and get them to check it out on their computer. Will get the gearbox oil and filter changed too for good measure.

Does your TD6 still have its standard 18" wheels or has someone put bigger wheels on it?

Might be a completely different set up, but I had a BMW with the same engine and similar judder to what you describe, turned out to be a broken engine mount that was apparently a common problem with them, might be worth a quick check to rule it out

Bemble said:

Does your TD6 still have its standard 18" wheels or has someone put bigger wheels on it?

Click to expand...

+1 18" max on a td6

In fact +2 to oversized rims....there is even a Tech Bulletin issued by Land Rover as it is that common - and bad!!

Thanks for your responses chaps!

I took the vehicle on 2 decent test drives and this issue didn't rear its head typically!!!

I have standard 18" wheels on there, albeit with slightly oversized Goodrich tyres. But it doesn't happen all the time, and seemingly only when the engine is warm.

I'm encouraged that the gearbox hasn't been mentioned. Am I correct in my assumption that if it still happens in N or P that the box is not engaged so I can rule that out?

Thanks again,

Tom.

In N or P, there is no drive by the gearbox, but it is still 'connected' to the engine via the torque convertor...this turns a shaft inside the box...which in turn turns the drive packs (packs are groups of clutches) when a drive gear is selected, hydraulic pressure pushes a piston in one of the drive packs to clamp the clutchs together and this then rotates the drive pack to turn the output shaft (in its very very basic terms)....
So when in N or P, none of the drive packs are engaged and hence the output shaft doesn't turn...but there are still rotating shafts inside the box.

But your vibration most certainly won't be caused by the box in N or P.....it is either the oversized wheel issue or you have a slight misfire in the engine.

Thanks Saint.V8,

That is really helpful (it must be if I can understand it)!

Will get it into the garage for diagnostics but looks like we won't have to cancel our holiday to pay for a gearbox just yet!

I had this same problem several years ago . Steadily got worse over time and turned out to be the no 1 injector was sticking

When I he an idle judder it was the torque converter, but you could see on the revs of the engine hunting slightly.

Mick

Could it be the lift-pump is tired and the only thing stopping it stalling is the ECU adjusting the FIP? I assume there is a lift-pump on the L322 and it is possible to check how well it is working?

My TQ is very much on its way out (admitedly mine is a petrol model, but principle is the same) and I suffer no judder at idle.

Get the car onto diagnostics - on live data, at idle any injector showing a positive value of 3.5mm3 needs swopping out for a new one.They are shi-e,so don't even think of using aftermarket cheapo recon ones.
Bosch common fail injection...

It definately sounds like a faulty diesel injector, or possibly a fault in the diesel injector wiring loom. Needs putting on diagnostics to check.

I have exactly the same judder as you describe, put my IID diagnostic tool on and read the live data values for the Fuel Comp. I'm getting an overfuel reading of +7 mm3 on cylinder 2, so gonna get it checked out soon at my local indy garage, when I've got a bit of spare time (and pennies!).

Easy to test if the injector or loom is at fault, by swapping the suspect injector around with a good one and seeing if the overfuel moves with the injector or stays put.
Replacement loom is around £150 and a good remanufactured bosch injector is about £180 (or get a new one if you can afford it).

Thanks again for your responses.

It's going in to the garage this week so I will let you know the results. Just to confirm, this only seems to happen once the car warms up, I'm guessing (with my very limited knowledge) that a faulty torque converter would display the symptoms regardless of temp?

Tom.