1995 4.3 timing issue

I have a 1995 S10 Pickup with the 4.3 Vortec. We just went through the engine, re did the heads new timing chain and gears. We got it back together and started it was running very well re connected the computer wire and was watching the timing mark with a timing light, I accelerated the engine,the timing retarded and would not advance, it backfired through the TBI and now will not start. When I tried to start it I checked the timing with the light and it was no where close, reset the distributor to align with #1, the light shows it is on the right mark but it will not start. :banghead: Help

Try setting the ignition timing with a slight advance (like 5 degrees or so)

I tried that, no luck. Possibly bad ignition module?

I tried that, no luck. Possibly bad ignition module?

That's possible too. Have you checked the spark on the plugs? If it's weak or nonexistent it could be the module. Check all of the connections, make sure everything is connected and check for corroded terminals just to rule it out first before you get into messing with the ignition module.