G'day all...new to this forum..trying to trouble shoot my brothers car issues..95 C280..engine just started surging while driving with check engine light "on"..and now a strong fuel smell..i got him to buy new 02 sensors 2 years ago, but they still aren't installed..i think that will cure the fuel problem, but the surging is an odd one..yesterday I took the plumbing from the air box to throttle body apart and cleaned it out with carb cleaner..the throttle butterfly was pretty dirty along with the air filter..I try to get him to do a little maintenance on the car..he just drives until something goes wrong...it's been trouble free for 2 plus years, but now things are starting...any thoughts on the engine surge would be gratly appreciated...!!!!!

 

It could be the Air Flow Meter. I've heard of guys having this kind of problem and going through way too much gas. Changed the AFM and it it was like a new car.

For some reason, the Overvolt Protection Relay can cause this too I think. . . not sure how I know that though.
B