93 Ram 150 #5 and #8 cylinders won't fire!

[DRR]

I am an auto tech and have been for 12 years, but this one really has me stumped. This truck came to me from another shop with many new parts on it already so they had obviously given up. It would not run when I received it and I replaced the oil pump drive gear and bushing which runs the distributor. There is a TSB on that one and this truck was showing all the signs and the ignition rotor had about 3/16" of slack which is the reason I changed it. Anyway the truck at least runs now but there is no spark coming out of the distributor cap for #5 and #8 cylinders. Coincidentally they are straight across the cap from one another. The cap is new and I checked the continuity from the inside of the cap to the outside and all is well. The terminals on the inside all have the little swipe mark on them (as the spark jumps across from the rotor to the terminal) except for #5 and #8 which to me means that there is nothing coming from the rotor even.

And yes I have tried another distributor pick-up coil because I had a good used one on the lot, but it was the same.......

Any ideas on this problem would be much appreciated.

Thanks

[1thunder]

did you check for spark with a spark tester and if so did you set it at approx 50-60 thou gap and check wires and did you index distributor as per service bulletin this is extremely important but are 100% sure it's a spark issue and not a fuel injector plugged i have 30 years for dodge in northern ontario also and usually find injector problems in these older vehicles you can remove them and clean them with a good decarbonizer and blow out and good as new

[DRR]

Ya I tried spark testers at the the plug end and the distributor end. There is no spark coming off the rotor inside the cap as the terminals are untouched while all the other terminals inside the cap have the swipe mark on them where the spark is jumping across from the rotor to the terminals. Like I said, the #5 and #8 are across from eachother on the cap and I really think that its related some way. Maybe the rotor speeds up momentarily while its passing this point? I really don't know.
the wires are ok as well....
I did the proper indexing twice to be sure and the sprk plugs in those two cylinders are wet with fuel so I know its getting there.

[1thunder]

did you check the distributor shaft for being bent or too much play in bushing and did you replace the oil pump shaft bushing and not just the gear assy