truck keep backfiring

[d.a.m]

it a chevy 350 throttle body  motor ran great sat for a few month it idle great starts rite up but when i put it in gear and give some gas start popping new plugs wire cap rotor timing good firing order rite

[paul]

tune up? sounds like there might be condensation under the cap

[J.C.]

Did you time it at zero with the wire unplugged

[Jjay78]

 fuel get water in it??

[d.a.m]

Did you time it at zero with the wire unplugged

no

[J.C.]

there is a tan wire with a black stripe, that has a connector you need to unplug first. thats the ESC, electonic spark control. the plug should be close to the distributor, since the tan/black wire goes into it. just unplug that, set timing at 0*, then plug that wire back in.

[KORNBREAD]

fuel get water in it??

most the time thats what happens. Member on here a while back had issues with stuff like that, tried everything people on here could think of and turned out his truck had water in the tank. 

[d.a.m]

i drained the gas tank, but Im going to try messing with the tan wire and see what happens, thanks for the help guys

[ToughBowtieTruck]

there is a tan wire with a black stripe, that has a connector you need to unplug first. thats the ESC, electonic spark control. the plug should be close to the distributor, since the tan/black wire goes into it. just unplug that, set timing at 0*, then plug that wire back in.

Some trucks depending on the year have this connector taped onto the harness near the computer, behind/under the glove box area.

[Colorado]

This is exactly what my Blazer is doin. '92 4.3 vortec......