Could it be this ?

Hi Gents

Recently done a thread where i asked what could be the problem with my disco TD5 loosing power when towing a Eldiss Crusader Storm caravan. Well this past bank holiday again i took the disco and caravan to a site and was again hassled by under performing disco. Talking to someone in the next pitch to me and he suggested it may be the air inlet pipe split... I have never though of this and was wondering if you guys knew where i can locate this and is it possible to see for myself if it as.

I can also confirm when my disco looses power the revs stay normal so i think that pretty much rules out any clutch probs, beside she had a brand new clutch system fitted last year.

Any ideas ?

Any feedback is so appreciated

He could mean the pipe between the turbo and the inlet manifold. On the 300tdi I believe it would make it pretty well undrivable but on the TD5 it has less effect. But with the extra boost needed for towing, a small split might have a significant effect. Again, on the tdi, the inside of the pipe can delaminate, partially blocking the airflow. Don't know if it happens on TD5 but should be easy to check.

I think they cured the de-lamination on the TD5 (I could be wrong!!) but it's the first place I'd look, and then at the oil ingress to the wiring loom fault. Search the forum for lots of info about this.