[lijoe]

what causes a mustang to idle rough is it vacuum problem i have powerdyne s.c.24#inj.i never changed the fmu when i put the injectors in could that do it.when i rev it up it drops to1200 then down to about 850 900 then i just goes up every know and again

[GTRaptor]

When you changed the injectors you changed to a calibrated MAF?

if not thats the problem.
Hows your AF ratio?

[lijoe]

ya i bought the new calibration for maf and the a/f ratio i dont know what do i need a a/f gauge i have adjustable fuel reg and tried from 36-45 and still prob.it wouldnt be the s.c.fmu cause its at idle right.i got egr on the codes chaged that and still a prob chaged o2 sesors the air bypass valve at the throttle body so i guess next is getting a a/f gauge right.

Originally Posted by GTRaptor

When you changed the injectors you changed to a calibrated MAF?

if not thats the problem.
Hows your AF ratio?