This is sticky territory. You may be dealing with many different offices within one company.
If your car is a 92, it is out of warranty by about 5 years. I'd say they could learn from your parts, but the likelyhood of them helping you with the repairs is VERY remote.
I am NOT on their side! I think that there very well could be a problem with some engines and the timing chain, not to mention the wiring harnesses and the evaporator cores!!!!!!!!!!!
But, I think that they will pull the corporate card here and say "it made it out of warranty".
I just don't want you to waste YOUR valuable time!
ASE CERTIFIED MASTER AUTO TECHNICIAN
MERCEDES SPECIALIST 11 YRS