occasional misfire

Hi,

I get the occasional misfire at higher revs in 3rd or 4th when accelerating up steep highway grades. It's not enough to worry about but my friends car also has the same problem.

I have the '95 4.0L Sport with around 20K on Splitfire Plugs/Wires and 2K on Brass Cap and Rotor Set. New TB and FIPK (great combination) and new Fuel Filter and 02 Sensor.

It drives great and is currently getting good mpg around 17mpg average. I tried some injector/ignition cleaner to see what would happen (no difference). I haven't tested injectors or tested compression but as the engine is running so well otherwise...

Is a medium load / high rpm occasional misfire in 3rd/4th gear something to spend time on or normal....?

I'm thinking of new vacumn pipes, coolant hoses etc in the near future as they are all the original 9 years old. Might even do a bit of heat shielding around the injector plugs as on later models.

thanks

Mark

I also have a 95 sport... I hav had this problem for a while too. My misfire usually happens during lower rpm when going up a hill in OD. I replaced the plugs, wires, cap and rotor. This fixed it for around 30k miles, now it is back... I guess i need another tune up... any other ideas?
~Joe~

My 95 would start sputtering as I reached the end of any long hill, or when accelerating really hard, such as on a freeway on-ramp. New (well, not NEW new, just different...wouldn't want to go overboard!) MAP sensor fixed it.