I had a random misfire and I finally had it fixed for a little the other day after changing the fuel filter and the crank sensor, but then it started to misfire again. Now a couple days later on my way home, my RPMs dropped and it felt like my car wasn't even on. I turned it off and now it won't start. I used a spark tester and there was no spark. It cranks fine, the timing chain is intact, plugs, wires, cap & rotor, crank sensor, and ignition coil are all new, and I took the swapped the ICM with my Jimmy to see if that was the problem, Jimmy still runs, Blazer still doesn't. Any ideas?

 

Sounds like one or more of the parts you installed recently is faulty. I would pull the cap & have a good look at it. Aftermarket cap/rotor parts are not the same quality as OE AC Delco parts.

 

Turned out to be my ignition coil, got it running, but still feels like it's idling rough, I'll wait to see if any codes come up.