1995 gmc 1500 5.0 timing issues

[smokie2]

Installed new timing set, plugs, wires, cap,rotor. Set timing runs good until I hook up the set timing connector them it runs terribly. What gives

[93gmc$$]

You have to do it in this order.

1. Engine off

2. Disconnect SET TIMING connector

3. Adjust Distributor to rough timing (0 TDC on the V-6, don't know for the 5.0)

4. Start Engine

5. Check rough timing with timing light

6. Tighten down distributor bolt

7. Shut off engine

8. Reconnect SET TIMING connector

9. Clear DTCs

10. Start engine, rev to 1500. After that, drive a few miles at various RPMs to give the computer a chance to re-learn.

[smokie2]

Did it in that order and when I start it after the set timing connector is hooked up it runs like the distributor got torn 180* I didnt install the timing set but if he hit tdc on the exausy stroke instead of the compression stroke would that cause this

[smokie2]

Will it hurt the engine to leave the set timing wire unhooked

[grampadirt]

Is it possible for you to make a short video of the timing mark in action,I'd like to see what it's doing.