formula94stef

my 1994 formula 5.7 auto.runs bad after the warm up(hesitation like a misfire) ,when cold she run better.
ive change the plugs,the wires with new delco parts
opti msd pro new,coil and icm new
fuel pressure tested 42 psi koeo,35 idle
new fuel filter
compression tested 210 to 215 psi all 8 cyls
with the maf unplug no change
ect sensor new
injectors ohmed all 8 at .014 ohms
whats else could do that please help

djjab57

iTrader: (17)

Same thing i went threw, Recheck your plug wires especially 2nd one on passenger side. It kept getting burnt on the header. well if you have headers

LT1nitrouZ

does it misfire in neutral or when it isnt under load?

86formula

iTrader: (3)

o2 sensor, does it run fine at WOT even when its warm?

formula94stef

when its not under load its less noticeable

formula94stef

at wot it ran definitely better even when warm but not perfect it have a tiny miss

myltwon

iTrader: (1)

if it's running bad after warming up I'd look at ignition components prone to heatsoak (ICM, coil, etc) or a sensor that is only used in closed loop (O2's, etc.)

formula94stef

coil and icm are new and spaced from the head with 2 washers each side
but the 02 are originals