MY MERCEDES CLK 320 RUNS BUT AFTER AWHILE THE IDLE DROPS AND WHILE IM SITTING AT A RED LIGHT IT CUTS OFF AND WONT START UNTIL 30 TO AN HOUR LATER

try Ebay world wide search

If the airbag light is on something in the system is broken. Go to AutoZone or similar and have them scan the airbag system for codes. My guess would be a faulty seat sensor or a faulty seat belt sensor

Sounds like the crankshaft position sensor needs to be replaced. They are a common problem with the Mercedes. That sensor is the one that the engine control module looks at to see if the engine is running. When they get hot and stop producing a signal the engine control module thinks the engine is not running and shuts of the fuel. After waiting awhile they cool down and the vehicle will start up again. I've changed many of them when I worked at the dealer. Tricky part is when there working and the car is running there will be no check engine light on or code stored. Usually will only have the code when the car won't start. Let me know what you end up finding out on it but that would be the first place to look and probably the cheapest.

My seat belt as well as the latch is stuck on my mercedes 320 clk. Any suggestions on how to fix?

you will need to reprogram system

i have a 2000 clk320. it would not start sometimes, the engine would crank but it wont start. but after an hour or so it would start. sometime i'll get somewhere park, and come out an hour later and the engine would not start. if your having the same problem, take it to autoparts store ex: autozone or kragen. they could check your battery for free. and if its not the battery. than it could either be your fuel pump. or the crank position sensor. good luck. hopefully this help.

This is probably your starter.

Check out the crankshaft position sensor

You could have a defective fuel pump, when they go bad they can draw enough current to fry the relay contacts, so I would suggest you test how many amps the fuel pump is drawing, I have fixed this very issue of repeated relay replacements, it was always the pump was shot.

faulty ignition switch. You will have to replace it.