ugh my service engine light is on again somthing to do with emmisions on 2003 Ford Mustang GT

my gt sounds like some one is strangling her when im in gears 1-4 shes fine but when i get to gear 5 she sounds like shes getting way to much air or not enuf air does any else have this problem or a solution to it

Asked by for the 2003 Ford Mustang GT
3 answers 1 comment
review when last tuned. run diagnostic. lookin for prob. with air/fuel mix. check intake hoses.
could possibly prob. with cat. conv. diagnostic will confirm or dismiss.
Any kind of mods. been done to air tube and air filter? "Sounds" like a problem you say but is it runninng ok?
yea shes runing fine she will get up and go when i ned her to but sounds like shes being choked out when cruisin
scan codes and post so we can adv