Salih, does your friend have a straight 6 cylinder or a 730 V8 engine?
I assume it is a V8 engine.
What are actually the problems that you want to know that?
That one has a mass air flowmeter . It looks a bit different than the one from the 750, but here is a testing method for the MAF of the 750. Hope that helps
http://shrubbery.student.utwente.nl/...leshooting.htm
By the way: what happened to your window lifters after I informed you some repair and checking possibilities?
Best regards to Northern Iraq