98 expy 4.6. when crusing with no load i feel a miss in the engine. if a floor it it dont miss a beat. just seems without a load and under 2200 rpms. i had no codes. fuel pump and filter, mass air flow sensor and plugs are new. im out of ideas.

 

Have you given the TPS (throttle position sensor) a try?
It can give a miss in a given position in the throttle. Maybe one speed and not another.

 

thanks, i will giver er a shot.

 

Plug wires shorting out? I had an issue with my 99 4.6 returning from a long winter trip in wet weather. Felt like I lost a cylinder, no codes, buck like mad under 2000 RPM but run much better with the OD off and RPM's at 2500 or 3000. Cleared itself on the way home. CEL flashed a few times but threw no codes. Took the local mechanic 2 visits to get it to miss. New plugs and wires (85K) and all's well again. I know you did plugs, how about wires?

 

i didnt do the wires. they "looked good". i think i will give that i try. i tested the tps and thru the whole motion it passed.

 

coil pacls. thats what was wrong with ours and we replaced them and it worked perfect. READY TO TOW THE NEW 25ft DONZI

 

is it an automatic with OD? Could be the trans "hunting" if the speed is right on a shift point.