Thread: A question for the Td5 Guru's if I may

You should replace it.
There was a thread some time ago about this topic.
But the aim of the WGM is to give greater boost at lower revs by reducing the apparent boost seen by the waste gate module. AFAIR this is done by the ECM pulsing the pressure from the manifold to the WGM so that it is reduced on the output ie wastegate side and so reduces wastegate "creep".

On high boost cars apparently this does not work as intended but mine has 21lb and IMHO it is fine.But for a stock boost car it is helpful.
Regards Philip A

Check the hose between the turbo and the i/c at the i/c end for early signs of internal delamination. The higher boost with the WGM operating may be enough to pick-up rubber causing partial blocking of the airflow.

Originally Posted by Graeme

Check the hose between the turbo and the i/c at the i/c end for early signs of internal delamination. The higher boost with the WGM operating may be enough to pick-up rubber causing partial blocking of the airflow.

All the turbo hoses are about 5k km's old and are pretty blue silicone ones.

How is the fuel pump? I once removed the fuel temp sensor to fit a pressure gauge looking for the cause of similar behaviour with a friend's TD5, only to find that the fuel pump was not pumping at all.

Originally Posted by PhilipA

You should replace it.
There was a thread some time ago about this topic.
But the aim of the WGM is to give greater boost at lower revs by reducing the apparent boost seen by the waste gate module. AFAIR this is done by the ECM pulsing the pressure from the manifold to the WGM so that it is reduced on the output ie wastegate side and so reduces wastegate "creep".

On high boost cars apparently this does not work as intended but mine has 21lb and IMHO it is fine.But for a stock boost car it is helpful.
Regards Philip A

I've put another new WGM in and it seems a lot better. I've also given the MAP/IAT and MAF a good clean although they looked pretty clean to me. I've had the waste gate actuator off and it moves smoothly and seems OK without proper testing. I've also set the rod to 12 exposed threads (it was 11).

One thing to note though is that the small hose from the inlet hose to the top of the WGM was quite oily. Perhaps the crank case breather valve and the turbo itself could do with a bit of further investigation.

It's probably worth keeping in mind that it has done over 400k km's so it probably "breathes" a fair bit by now. It has had a new AMC head about 6k km's ago though.

Mark, is the exhaust all original and does it have a Cat fitted?

Paul.

Originally Posted by Graeme

How is the fuel pump? I once removed the fuel temp sensor to fit a pressure gauge looking for the cause of similar behaviour with a friend's TD5, only to find that the fuel pump was not pumping at all.

Fuel pump is brand new (<5k km's) and genuine. I have noticed though that it is hard to start (about 10 sec of cranking) after it's been sitting overnight. It starts instantly if I start it after an overnight rest, turn it off and leave it for a while and restart it. My guess that there's air leaking into the system somewhere. It also drops a few drops of fuel from around the fuel filter overnight. I've only noticed this over the last couple of nights because I've been parking it on clean concrete and not on the grass.

Originally Posted by harro

Mark, is the exhaust all original and does it have a Cat fitted?

Paul.

No CAT The exhaust is in good condition and the flex pipe below the manifold is less than two years old. It's an August 2000 10p engine.