Plasticman

03 LS1 automatic with 30K miles that intermittently lays down under full throttle (pulls fine for a second or 2, then "blah"). Engine just goes severly flat - call it a bog. It does not die and will continue at lower throttle just fine. No unusual noise or pinging.

It has done this twice on 2 different days. Each time, I "tested" it again, and it then pulls just fine. Today I hooked up a fuel pressure gauge, and tried it several times, and of course it ran great. Saw 60 psi nominal, with sometimes a slight drop during full power to 57 psi.

No codes are set, other than a U1160H, which should have nothing to do with this.

Only mods are a Callaway cold air intake, Corsa catback exhaust, and the Diablo "standard" tune (to eliminate torque management) running 93 octane Shell.

My first step is replacing the fuel filter, but doubt that is the issue, since it is so intermittent.

Any and all help is appreciated!
Plasticman

Plasticman

8VETTE7,

I should of mentioned that I am one of the lucky (early) 03 Vette owners, with the relatively "easy" to replace fuel filters......

I just checked the glove box (again) and FFS is not listed, but my VIN is later than your number (mine is 11480X). And I have just looked at the fuel filter, so I know I don't have the later FFS.

Thanks,
Plasticman

optimum01

Could be the overdrive kicking down. Try it in 3 instead of OD. A tuner who can do a transmission tune can definately make an improvement also...

Plasticman

I should have also mentioned that this is from a dead stop (it is strictly upshifting during the "runs", and it is the engine that is laying down).

Thanks,
Plasticman

Kreeess

try to get a hold of a tuner see if he cant tune it out for u, process of elimination. try fuel filter if it hasnt been changed and might as well throw in some techron in it check all plugs clean maf etc, my car had similar symptoms to yours i changed up everything only to have it come back each time, finally got a tuner to tune the car and shes never ran better! give it a shot, you cant go wrong with a tune for the car