hey guys. i took off my fmu to clean it because i havent driven the car in a few months.

i put it back together and i blew threw the fuel line and i could blow air through it. should i be able to do that?

thanks,
jeremy

 

i think ive got it figured out guys.

i can blow through it untill i put some pressure on the piston (simulating boost press.).

so it is doing its job, which is to block off the fuel return line under boost. right?

jeremy

 

Right. The FMU blocks return of fuel to boost fuel pressure. It does this when positive pressure is applied to the diaphragm orfice.