what is a MOT valve? and where is it on my c32
I have a tapping noise coming from the rear of my engine on the passenger side. the car sounds like a diesel truck. my car is a us model '02 c32 and the noise is not coming from the engine (lifters) or from the purge valve. i am trying to figure out what the noise is and it's driving me friggin nuts. i have searched other forums and noticed that a few others at another forum mentioned the "MOT valve" may be bad. i have no idea what this MOT valve is or where it is located. thank you



