Thread: TD5 lack of power, slow to rev

Do you have access to a Nanocom to confirm sensor readings? The AAP, MAP, and TPS can all give erroneous readings that will affect power (also need to confirm the new MAF). RAVE gives the input output voltages to check with a multimeter if no Nanocom.
Otherwise, check everything you can, such as air filter blockage, collapsed turbo pipe, blocked intercooler, whining/noisy fuel pump could be giving low pressure to FPR.

There are a number of things that could have been missed in the head exchange. Was it remapped?

There's lots to check, and plenty of real experts on here (not me) will be able to assist if you can describe the symptoms well and list what you've checked.

How cold is it where you are?

Cheers Discofender

Something is awry. DJ has covered the obvious checks. I would add that I would expect boost before 2600. I’m wondering who did the head. Could the timing be a tooth out? Were the injectors coded properly? ( Don’t think that would cause your issue but…). Check your f the exhaust is restricted.
Some random thoughts. I am no expert either. If you are keeping the car I would recommend getting a Nanocom. They are not particularly user friendly but they are pretty much the only diagnostic tool you can get for a TD5 and pay for themselves eventually.
if you’re near Quebec there’s a LR mechanic at Sherbrooke.

Really hard to Diag this stuff remotely without any hard data.

Based on the symptoms and history my first guess would also be timing.

It won't be incorrectly coded injectors.

If you unplug the MAF and MAP/IAT the ECU will default to some programmed readings that are low, but still shouldn't stop it revving.

Other things to check if not mentioned above are:

Is the fuel pump running.

Are the injector bump settings correct.

Does it have bad blowby.

Are there any errors logged in the ECU.

They aren't in order, so pick the easiest quickest ones first.

BTW, 5 pumps on the throttle with the ignition on should put the fuel pump into a purge mode and it will cycle on and off for a while.

The defender has no soundproofing around the fuel pump (or anywhere else) so the pump is really easy to hear, possibly even when you are in the car with the engine off.

A number of these things are listed in the 2 posts above, not trying to steal anyone's thunder, just reiterating....

Originally Posted by nakedbarra

....
The waste gate is free and turns smoothly.
Any ideas as to why it lacks power and is slow to rev up?
Cheers

I would double-triple check the wastegate.
While its free moving, have you checked length of rod.
This would be first go to point.
You said head done prior to ownership, maybe someone previously had turbo disassembled, and when put back together they got the length of the rod 'too long'

If the rod is just ever so slightly too long in length, it could be set to just slightly open the wastegate and instead of pressure spooling up inside, it's leaking paste wastegate and not giving reasonable boost lower down.
Once you get to that 2600rpm stage tho, there's enough pressure in the exhaust to give some boost.

Easy to check, disconnect rod at wastegate and make sure that the wastegate actuator and rod length has some 'pulling' force back, to force the wastegate shut.
That is, if you disconnect the rod at the wastegate and can, relatively easily get the rod back onto the wastegate arm .. it's too long. You should have to pull the rod out of the actuator just a little to hook it onto the pin.
(or do it the bludgers way and just add some compressed air to the actuator to push it out and hook it to the pin).

Originally Posted by shack

A number of these things are listed in the 2 posts above, not trying to steal anyone's thunder, just reiterating....

Wouldn't worry about that. You probably do have "expert" status.

Arthur makes a good point re the wastegate actuator. RAVE specifies a number of thread turns, which I can't recall atm.

10 comes to memory but I can't be sure

I still fancy the fuel pump as the cam driven injectors can syphon fuel from the tank, so higher rev's means better fuel supply. I actually got a speeding fine uphill on a freeway when mine wasn't working properly! You should hear the pump whining under the car when you turn the key on.⁹