multiple random misfire

[r2987v2]

i have a 1998 5.4 exp with 175000 on it, full exhaust, intake, dynotune
for about a year now it has had hesitation, bucking and multiple random misfires
mostly under load, the only way i can drive it is when i hold the gears longer and shift manually (this prob happened before the dyno tune)
i've changed coils plugs fuel pump cats o2 sensors every sensor except the knock sensors the fuel filter 4 times and have run 93 from several stations
the problem is worst when the engine is cold, i have no trouble codes
my guess is the computer, any ideas?
oh yeah and it also burns a quart of oil about every 800 miles, it burns more oil than the ATF burns branch davadians

thanks for any help

 

[Brown Bear]

have you check the fuel rail? clean injectors?

 

[FordandPolaris]

I would have to agree, check the injectors. Also look/listen for vacuum leaks. The fact that you are burning oil so quickly would suggest that you have a bad piston ring. If it is bad enough, that piston will not hold compression. Therefore this would cause a misfire as well. It would be worth while to get a compression tester and make sure all of the cylinders are the same. If you have one that is much lower than the rest... it would be rebuild time.