Dilraj

Hey guys I’ve reached a dead end on my 2003 mustang gt I had got some bad gas in my car and it started misfiring and running bad only under load and when it’s warmed up when it’s a cold engine no misfires, I have put fresh gas in it after running the bad gas out and I replaced my coils and my fuel injectors it made the car run better but same issue when it warms up and I go to floor it it wants to turn off and sputters if I turn the key on and off real quick and rip it it goes fine than back to misfiring again it’s rlly weird to me cause it a little different then a miss fire I have no codes
if u slowly climb to 4K rpm and hit the gas it just takes a **** on its self and wants to turn off
any ideas what it could be ?

sweetbeats

Have you checked your fuel pressure at the rail?

Dilraj

yes I think I have found the problem when I checked my pressure for fuel it drops from 40 psi to 7 psi under load I have ordered new fuel pump assembly and filter

Derf00

I would've started with the fuel filter. You can have high pressure and low volume (idle) and low pressure from high volume demand (any other RPM)

sweetbeats

+1 to that ^^^^^^^.

Dilraj

fuel filter was already changed not that long ago