Alright,

I just finished a complete tune up on my rig. (Plugs, wires, cap, rotor button). I also have put some fuel system cleaner in my tank and i am letting my truck run in hope it does some kind of cleaning to the fuel delievery system. After the tune up, she is still running rough (obvious lope and miss). I am assuming it is some kind of vacuum issue or dirty fuel system or both. I was hoping someone who have a good idea as to where to start. An and all help would be great!

Thanks.

P.S. I installed a new VSS and I now have a working speedometer!!

 

fuel filter, try it

 

Excellent. Thanks

 

also, run some seafoam thru the gas tank, reccomended before you change the filter because you could possibly foul your new filter.

 

Seafoam could foul the new plugs too. Assuming you have dual tanks, does it do it on both tanks? If you have a single tank, disregard that

Then there is the obvious stuff that we all sometimes miss. Are all the plug wire boots on snug? Is the new dist. cap locked down right, etc... I had this happen once and it turned out to be a cracked coil. For future reference, easier to check for a cracked coil with a spray bottle of H2O than with your bare hand while motor running