TD5 Auto Question

It's a bit of a puzzle. Obviously if the modulator or hoses to the actuator failed you'd be seeing overboot so that eliminates them as suspects. I haven't had the "pleasure" of dealing with a wastegate sticking open, but you'd have to think that it would be slow to pick up boost, so it would be worth investigating. You'd also expect to get a bit of a whistle under boost if there were hoses leaking.

The 55-60 degree IAT is a bit of a concern. Unless it was 40°C or more when you were testing that looks like the intercooler isn't working efficiently. The only time I saw 60+ IAT on the weekend was on a reasonably steep climb (Girvans Cutting on the Calder heading south from the Castlemaine turnoff for those who know the area) where the engine was sitting on 14psi boost at 110kmh for well over a minute. Ambient temps were mid-high 20's. Even that kind of performance has got me looking at a bigger intercooler.

I think of two ways for the intercooler to not be dropping the temp sufficiently. There might be more. First is a clogged intercooler which would restrict flow and mean the intake air wouldn't be cooled as much as with a clean intercooler.
The other possibility is that there is a air leak on the outlet side of the intercooler which could result in a larger volume of air passing through the cooler and less temp drop. But really that is just guess work based on the observed temps and pressures.

Perhaps have a look at what the IAT was doing on your D2 on the run you mentioned. That should give you a decent reference point to compare with, and certainly a better one than my d2.

cheers
Paul

Just a thought... What about throttle position sensor. TD5 is drive by wire, and I believe there are two derivatives of this sensor 2 pot and 3 pot for later versions. Nanocom should give sensor readings, or swap with working vehicle (provided sensor is same type).

Quote:

---

Originally Posted by antond

Just a thought... What about throttle position sensor. TD5 is drive by wire, and I believe there are two derivatives of this sensor 2 pot and 3 pot for later versions. Nanocom should give sensor readings, or swap with working vehicle (provided sensor is same type).

---

The accelerator readings are included the recording that was posted up and reflect the throttle inputs that were described (i.e. flat to the floor to get boost to build up).

http://www.aulro.com/afvb/attachment...1&d=1365753982

As you can see it's taking something like 15 seconds from application of foot to the accelerator to reaching maximum boost.

cheers
Paul

So I deliberately wound my wastegate out so that it would be in the semi open position, to see if behaves like Jadan's vehicle. Nanocom data capture isn't exactly the same, due to different maps, but the air flow is sawtooth on the Nancom compared to my baseline data capture. This is in line with the problem child.

Jadan is also either going to wind out the wastegate in line with my tests to see if the behaviour doesn't change much or just go straight to the possible culprit, a leaking wastegate valve, when time permits.

For others, TD5 wastegate - Defender Forum - LR4x4 - The Land Rover Forum talks about one way of freeing the wastegate.

Has any one given any thought it may be in limp mode? Remember he is new to the car and has no prior experience with the beast.

No M&S lights and no faults reported by Nanocom. Also works through the gears. So not in limp home mode. As indicated, deliberately opening the waste gate to make it leak gives similar feel in a good car.