TD5 powerloss (again)

After going brilliantly for a few days after bypassing the wastegate modulator the power problem is back ..again!....no fault codes, fuel pump voltage works, same if not worse when the MAF is unplugged same with the AAP unplugged. Wastegate is free (really free). Put a new actuator on it, new injector harness etc, new throttle pedal. Wiring looks all good.

So now I have exhausted all avenues and had this problems since last October I just wondered I would have one last crack and ask everyone on here for anything I maybe missing or perhaps any ideas?

Thanks for all your help.

How strong are the turbo pipes? Are they not delaminated or cracked or leaking at a joint? Also with the AAP unplugged must be worst than with it connected except when it's overboosting(it's not like with MAF cos AAP open circuit means restricted boost) so if you have diagnostic tool read live data to see the MAP-AAP relation

sierrafery said:

How strong are the turbo pipes? Are they not delaminated or cracked or leaking at a joint? Also with the AAP unplugged must be worst than with it connected except when it's overboosting(it's not like with MAF cos AAP open circuit means restricted boost) so if you have diagnostic tool read live data to see the MAP-AAP relation

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Turbo pipes all feel stiff and no signs of delamination, it's so intermittent.

I unplugged the AAP and thought it ran better buy I was disproven when the power loss happened again, and now sure if it's because I unplugged the AAP but my AC fan is now running constantly.

When it occurs you I lose all use of the gas pedal, only option is to drop a gear and when it's gets to about 2500rpm she fires forwards .

I'm determined to keep her on the road just had to repair the ACE system, it's worth it but was challenging.

If the AC fan runs constantly the probem is with the engine coolant input or it's actually overheating and when the ECT input gets high the ECU cuts fuelling and you can't rely on the gauge cos it stays at the middle from 70 to 120*C while the overheating protection kicks in at 110*C... as i said the relevant thing would be a live data log to see what happens when the symptom occurs otherwise it's just a guessing game

My garage says the live data is fine and nothing to show why its doing it ......all things like MAF and MAP are fine apparently.

It's happen when cold or hot. It's now become a guessing game. No one seems to be able to fix it.

Just drove home from work and it's now constant and even turning on and off which used to reset it doesn't work now . But then tomorrow it will most probably be fine, Gutted with it now.

All it's journeys are on the dual carriage way 55mph, so I hope that keeps it's cool

Landrover6176 said:

My garage says the live data is fine and nothing to show why its doing it

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So those from your garage watched the live data while the symptom occurred and everything was fine then?

sierrafery said:

So those from your garage watched the live data while the symptom occurred and everything was fine then?

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So they say .....young mechanic.....however I'm starting to belive that the symptoms I described didnt happen whilst they had the car.

Sorry amateur question! But the engine coolant input. Is that done by the temperature sensor?

Landrover6176 said:

Sorry amateur question! But the engine coolant input. Is that done by the temperature sensor?

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By the ECT(engine coolant temp) sensor cos there are more temperature sensors on a D2

sierrafery said:

By the ECT(engine coolant temp) sensor cos there are more temperature sensors on a D2

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Thank you, so this would be worth replacing? But then if this was faulty would my temp gauage be all over the place.

Nothing is worth replacing untill it's not diagnosed, i told you how the gauge is showing, it is a possibility that the ECT sensor to over read and cause such trouble if it sends let's say 115*C while the real temp is 90 also it is possibe that the temp to go high for some reason, as the AC fan runs constantly there is an overheating fault code stored in the ECU which must be erased to stop it(unless it's some other reason for that) i dont like guessing games

I'm not enjoying this guessing game of time and money and keep replacing parts which doesn't improve the car. Dreadful that I can't seem to find the problem which bugs me. I dont want to say it but coming mostly from older BMW, V8s mostly, I would have found the problem alot sooner. I'm not sure why these are so difficult to diagnose. It's getting to the point where it's now the most expensive garden ornament I have. There just so many if buts and maybes. We started off with a driver demand fault so replaced the pedal, it solved the fault code but not the powerloss. ....I'm getting advice from it's a £6 hi/lo switch to replace the turbo haha. .....what's the most frustrating part is that it's so intermittent, it could go 4 days without a single hiccup and drive absolutely superb. Or it can constantly lose power. .....

Never plays up in a a garage though.

Although i would admit I still love her haha

I complain but I wouldn't part with it.

All you have to do is to catch the live readings when it happens

I did have myself a foxwell which unfortunately, due to a friend reversing over it I need to replace. I think in going to stick with the NT520, I know there is a NT530 but I've heard there problems with them.

If I remember rightly there is an SD card slot in the foxwell

Yes, you can record data with foxwell

That will be handy as I can hand it over to people of far more expertise with electrics

I do appreciate your help and advice.

Landrover6176 said:

I did have myself a foxwell which unfortunately, due to a friend reversing over it I need to replace. I think in going to stick with the NT520, I know there is a NT530 but I've heard there problems with them.

If I remember rightly there is an SD card slot in the foxwell

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Hi, I have a NT530 for my FL1 MY04 & D2 MY01 & I haven't come across any problems with it although it has suspension calibration in the menu (for the D2) it can't perform this function otherwise I find it great & as SF says it can store data to the SD card.

Have you looked at the inside of the boost hose that comes directly off the Turbo to the IC Pipe ...........

I have had a few TD5 motors in my workshop which have developed a tiny split internally and they blow up like a balloon inside thus blocking air entry, leave the vehicle for a while it then drives OK PITA to find that on the first one I had in That said, the boost hose balloning fault doesn't make them run the cooling fan .

Sad to say it but a lot of so called professionals simply do not understand how to interpret Data, I do this stuff day in day out, and a helluva lot of my work is sent here from other Garages who just can't fix anything a little off beat