Why does my car only like 93 octane??

[new97v6]

Ive had this car for over a month now and cant seem to figure it out. if i put regular in i can barely give it any throttle without mis firing like crazy and blinking ses light. when i put 93 octane in the problem just about goes away completely. the plugs and wires are both new and ive re-checked them many times and they are fine. anyone know what might cause this??? car has 100k on it.

thanks

[mcgs999]

Did you replace your coil packs? also have you run injector cleaner through recently?

[new97v6]

no i have not replaced the coil packs. do you think coil packs being bad would be affected by octane though? i have run 2 bottles of injector cleaner however with no change.

[black98V6]

does this just happen when the engine has warmed or is it prettymuch right off?

in order to have a misfire you either have a fuel problem, an air problem or a spark problem. Carbon buildup in the combustion chamber can cause detonation and I could see where higher octane might help but I doubt you have that much carbon buildup.

I'd be willing to bet it's a spark problem, you need to scan the codes and see where the misfire is, if it's random you got other issues, but it may just be in 1 or 2 cylinders, this could help you to trace down a particular coil if that's the problem.

[ August 14, 2003: Message edited by: black98V6 ]</p>

[new97v6]

it happens only after its at operating temp. if its cold i can go all the way to 6000 rpm. also only when under a load. if its in neutral i can rev with no problem at all.

[CamaroRob97]

YOu won't get the misfire in netrual. THere is no intial load on the engine.

[black98V6]

well this can be caused by a plug wire or coil also, I'm willing to bet that is the problem, go get the codes scanned and see if you can nail it down to one cylinder..