Dear all,

while looking inside the engine of my friend's '85 745 I have spotted a part which is missing in my '90 745 - preheater hose to the air cleaner box. Shame on me, I did not even know about the existence of this part before.

In my car the corresponding intake to the air filter box is just blocked by a piece of plastic which seemed to be factory.. No signs of any preheater attachments to the exhaust pipe.

Could anyone explain me what is the role of the preheater hose and how it's absence might affect the performance? The preheater issue seems to be really strange in view of the turbo intercooler, which actually cools the cleaned air down!

Thanks...