Recently CEL came on. I brought my car (99 C230 Kompressor) to Autozone and a mechanic that specializes in Mercedes and got it checked. Both of them said fuel tank pressure sensor failed. The mechanic told me to replace the gas cap. Since mine was too old to seal the cap, he told me to give it a try. Surprisingly, it seems to be one of the main issues of this failure. I did, but CEL is still on.
Is there only one fuel tank pressure sensor or a bunch? Is the sensor hard to replace?
Any comments/opinions would be highly appreciated.

 

Looks like my questions are always tough... No answers at all...

 

CHARCOAL CANISTER SHUTOFF VALVE. FUEL TANK PRESSURE VERY VERY VERY VERY VERY RARELY GO BAD.

 

Haven't been here for a while.. I got a reply!
Cahrcoal canister shutoff valve? I need to do my research more... Thanks for your reply!