NO Start, Rough Idle

[BDJack]

Started the truck up the other day and it was running really rough, bucking hard. Not just when it is cold, also on a 70 degree day. Plugged in the block heater to try and eliminate the gp relay from possibilities and now it will not start

Oh and wait to start light does come on, and tach moves very slightly, but moves regardless, could it still be cps?

Taking batts and alt out to bench test tomorrow. Any ideas? Would a bad batt or bad alt cause the truck to run like that?

Thanks

[NoLimits]

Bad batteries will cause it not to idle at all or start unless u can pull start it. You should find out if the PCM is throwing any codes.

Not sure what a bad alt would cause.