bad miss in 94 gmc

this is my first post so it may be long. i have a 94 gmc jimmy 4.3. it developed a miss over night i think . it was only noticeable at idle at first and wasnt erratic it seemed to be one cyl. i knew the pressure reg on the spider was leaking so i installed a new spider (also had leaking injector). miss was still there and exhuast smelled very rich and "eggy". replaced plug wires and plugs. one plug that was removed was wet like a fouled plug. also changed dist cap and rotor button. still have the miss and its getting worse. noticed smoke today white or grey in color. could this be a burnt valve . man i do need help on this thing . it has 176000 miles on it . :banghead:

I had a 95 S10 that had a rough idle and an "eggy" smell. I took it to a muffler shop thinking it was the cat. I later found the vacuum hose on the driver's side that leads to the vacuum reservoir had somehow been pulled off.

Did you change the nut kit when you replaced the injector spider.

Chances are the nut kit is now leaking.

It will foul the drivers side plugs so if the fouled plug was on the driver's side then you know that it is the nut kit.

i did change the nutkit because i noticed leaking on that side also i have not found any vac leaks but will keep lookin. thanks for the replies.

Go get a bottle of Redline SI-1 Complete Fuel System Cleaner and dump in a complete bottle and fill up the gas tank.

This will remove the deposits on your valves which is more than likely causing your problem and will clean the injector poppets.

Is the radiator low on coolant? White smoke out the exhaust is a sign of a blown head gasket and coolant getting into a cylinder.

collant lvel is good smoke is not constant but intermittent

I would reset the timing to zero with the timing wire disconnected.

Sounds like it is running base rich.

how do i do that . never done that before. shouldnt the timing already be set ? and will that cause one plug to be wet while the others are not? and will that also cause the constant miss?

i do thank all you guys for the replies this is a great forum lots of good info. thanks again