if you run your engine on idle and disconnect the mass air flow sensor while its running ant the way it runs dosent change does this indicate the mass air flow sensor is dead?

also when i leave the engine on idle and listen at the exhaust (aftermarket 3" one) every 2 seconds or so you hear a sort of popping coming from it and when i rev it it revs up fine but as it goes on it way back to idle its like brummmmm pop pop pop. but idles ok, bit rough tho.

can anyone help out?

its a mk6 escort by the way. 1.6 silvertop zetec.

 

I believe if your engine runs lumpy and disconnecting the AFM makes it smoother this points to AFM being dodgy.
How is yours running at idle for you to try this?

Checked exhaust for leaks?

 

it seems ok just a vibrates a bit. so i dis connected to anyway just to see and nothing changed.

 

Mine cuts out when i unplug it mate so that may be your problem

 

ive got the same engine in a fiesta, and mine pops alot on the way down the revs, me and luke 89 both have the same cars, they both do it, we can only come up with it being the air pulse system ?????