miss firing 1998 gmc jimmy?

[hunter]

i had to tap and heli coil the spark plug hole and i still getting a misfiring new plugs and wire and dis and rotor what could it be

 

[dangerII]

I believe you got the firing order off.Get a book or call a parts store or a shop to get the firing order for your engine size and year.I am wondering about what you said here did you say you replaced the distributor also?.If so you might not have it set right with number one cylinder.Check your timing mark on the balancer at top dead center align it with the number one plug wire but make sure your valves are in the closed position.Check to see if the piston is all the way up with a screw driver in the cylinder but don't put the screw driver in there while turning it over to get to number one.Tool stores have a thing what they call a wistle that blows loud during the time your trying to get number one cylinder to top dead center.It acts likes a compression gage hose that screws into the cylinder.After you get number one brought up on the intake stroke both valves are closed.Check your alignment with the distributor where it is pointing.I believe number one on this year is at the 7 o'clock position if your looking down at the distributor from the front while your up in the engine compartment.If you have any question email me at hgm20002000@yahoo.com