I just replaced both ignition coils. I've checked for continuity along the system. No wires out of place, fuses and diodes all check out. Last weak the truck just died at a stop sign. It cranks fine. The last tune up was not too long ago. The truck was running a little ruff before this but not bad. The check engine light code was 315(?). Something about the computer not getting power. Tried replacing the computer. Ended up putting the old computer back in. Don't know what to do next. Any ideas?

 

2.3l engine?
the computer you replaced was the ignition control module or pcm?

unplug the wire at the one spark plug keeping the other wiring in place as they act a return for the waste spark system.
install a spark tester on the to the cable and to grd...crank the engine and confirm spark or no spark at the tester.
if no spark:
koeo(key on engine off).. test for battery voltage on both coils red/green wires
-no power- this is feed power from the ignition switch so check at the ign switch for power