My brothers 94 300 e intermitently runs rough. it will be going along fine and then (say at a stop light) just bearly stay running. Then just like that it smooths out and runs fine. it was acting up as his wife was driving past the dealership so she stopped in and took a tech for a ride. He "knew what it was" and replaced the "smoken hot" , fuel pump relay, but that did not fix it. another thing, it only did it when the outside temp was above like 80 deg F, but now it is starting to do it more often and at lower outsside temps. ANY IDEAS.

 

Have them look at the ICV (Iddle Control Valve), either clean it or replace it....

 

no - is there any advice on how best to clean or check it.
It went to the dealer and they replaced the mass air flow sensor and it is still doing it. We are afraid they are just going to swap parts untill they hit "bingo" or we are broke.