C230 MB Kompressor Check Engine Light

a few months ago my car completely shut off on me at a stop light, check engine light came on.. i got the car running eventually and had it towed to the local MB dealer.

a belt was broken and needed to be replaced.. cost about $400 (what a rip)

now, three months later, check engine light comes on again every so often.. usually when i leave my car in park, and engine running...

yesterday, car was trembling and sounded like it was going to shut off on me, check engine light was on.... then i shut off the car, took out key, restarted car, no problems, no CEL and nothing happened..

my Service B is due in 600 miles.. and i'm taking it this wkd to get done.... i dont know how to even ask what else is wrong with the car as I dont wanna get ripped off my fixing something that isn't the main problem.. any help?????

car has 63K miles

possible mass air meter.

the car is okay now?

any findings from the dealer?

ask for more info like... fault codes, diagnosis results, etc.