New Defender ECU problem?

Hello there, I wonder if anybody can help with this one. I have posted this question elsewhere but no real solution as yet. I have a new Defender 90 CSW and it has an odd accelerator pedal action. Everthing is fine until you use more than about two thirds max throttle travel (even for a second or two) and then the engine changes mode...the accelerator pedal becomes less responsive and requires pressing down quite a bit further to produce the same performance as before. It stays that way until you stop the engine, then it resets. You can drive at motorway speeds amd it will not do it, unless you apply full power. Max power also seems down when this happens but I am not certain about this. The vehicle has been back to the dealer twice but they say it is just the emission control and there is nothing they can do. They claim that no fault codes are stored in the ECU. Can anybody shed any light on this? I have not owned this type of vehicle before so have nothing to compare it with.

If the vehicle is still under warranty then you need to get your dealers service manager to take you out in the car and show him the fault.A Td5 90 should be quite a lively car and be able to "scream" a bit when hanging on to a wide open throttle through the gears.It is not normal for them to go flat.There are several reasons that could cause poor performance that come to mind,including a stuck open wastegate,poor resistance tracks on the variable resistor tracks on the throttle pedal or perhaps the wrong injector codes programmed into the Ecu.None of these would 100% have to log codes,like I said it ought to go quite well - take it back and ask for someone to actually do more than read codes,suggest they do some live data displays whilst driving.This is the way to see what is wrong.
Good luck !!

l have the same problem with mine, its seems to go into low range mode if l take it over 40 mph in 4th. lts been like it for some time now.

the td5 defender has most of it's power on tap at even 30% travel range of the gas pedal. it goes into long travel mode as in low range for better control.

so during the first 30% of travel of the gas pedal, the engine can almost be like abt more than 50% power. the moral of the story is that it requires less pressure to get the same power as compared to a manual linkage.

but ya, back to the part of the ECU, ok i've never had this problem before cos maybe i've never floored the pedal. my rite foot is really light. maybe the engine will kick me for early change ups too. ha ha

Thanks for the replies. The supplying dealer says there is nothing wrong, in fact the second time I took it in the engineer who came out with me in the vehicle was quite cross, as though his time was being wasted. He did experience the "fault" but said it was just the emission control. "Rottenrich" though seems to have the same fault, and somebody has e-mailed me to say theirs is also the same. I will take it to another dealer and see if I can get them to put the diagnostic computer on it while driving,maybe that will show up something. There is obviously nothing really wrong as the vehicle drives fine apart from that, I guess the electronics are playing up.
However I have just done 250 motorway miles in it and can say that it's much nicer to drive and also performs better before the "fault" kicks in.

Have you had any luck sorting this out yet, mine went in for service the other day, l told them about this but they couldn't find anything wrong.

No as yet I do not have a solution. Can you do me a favour...can you look at the threaded rod on the wastegate actuator and carefully count how many threads are showing on it? I have a feeling that somebody has tampered with the adjustment on mine as the paint seal is broken. Please let me know your findings,thanks.

get them to check the postion & fastness of the pick up on the accelerator switch - the whole thing is a big potentiometer so they should also be able to check that the resistance values are correct.... The ECU has a different map when in low range - again get them to check that the transfer box switch is all correct.
If it's easier to fob you off than sort the problem they will take that option. Keep pestering them until it's sorted.

lightning said:

No as yet I do not have a solution. Can you do me a favour...can you look at the threaded rod on the wastegate actuator and carefully count how many threads are showing on it? I have a feeling that somebody has tampered with the adjustment on mine as the paint seal is broken. Please let me know your findings,thanks.

Click to expand...

l don't know if they will all be set the same, but l've got 12 threads showing.

Thanks for that. I looked at another one and it's the same as yours....12. That proves somebody has tampered with the setting on mine, (I have 15 threads showing) and is probably the cause of my problems. The ECU is detecting the excess boost and cutting the power.
I assume that if you do a chip upgrade it tells the ECU to accept the extra boost.
The vehicle was a dealer demonstrator,so they must have done it,the cheapskates!

Sounds like an interesting thing. Pardon my ignorance, but where is this thing located? Maybe i'll try counting mine.

Open the bonnet on your TD5 and locate the turbo, on the right hand side of the engine at the top, looking at the vehicle from the front. There is a heat shield covering most of it, but you will see a small cylinder about the size of an egg on the top of it. This is the actuator, there is a rod coming from it which goes to the top of the turbo housing. This rod has a threaded section with a nut at the end of it. Count the threads showing carefully and there should be about 12 if it's not been tampered with.