Stutter

BLAZE5338

MEMBER
FORD MUSTANG

I have a 88 mustang 5.0 HO speed density no mass air with bout 38,000 miles ive done some modifications to car and dont know why it stutters.First of all it doesn always stutter it seems to be only when i give it mid throttle or when i first start to go the motor stutters, it wont stutter if i punch it,It goes away but if i baby it it will stutter? sometimes the stutter wont go away once it starts stutterin unless i punch it? the mods i have done are underdrive pulleys,full racing ignition by MSD(witch i was told was the problem,not the MSD itself but my ignition system cause i was havin trouble before it was installed) Also have a cold air intake (BBK),Hedman headers with stright pipe exaust and flowmasters(no catalystic converters)now i was told it is either fuel or ignition, I changed the whole ignition and fuel pressure is good any suggestions i love this car and dont want to get rid of it over minor issues i just cant figure it out please help if you have any suggetions thank you.

1 Reply

INDYUKE

MECHANIC
416 POSTS

Does it feel like a general rough stutter involving all cylinders, or does it seem like it's isolated to one cylinder.

The reason I ask is because I ran into the problem on a 5.0 a while back. A fuel injector had a gremlin in it. The engine would stutter at low rpms and at idle, and only at certain times. Seems that ford fuel injectors are sometimes temperature sensitive, sometimes they stick, sometimes not. Certain ones will always plug themselves up because of where they are located (hot or cold environment) while others will never plug up.