HELP! My bad idle situation continues unchanged, and I've replaced everything but the carb and fuel pump... Dammit! So, does anyone know if a bad fuel pump, in additional to causing a crappy idle, would cause my truck to backfire during gear-shifts and engine-braking? It seams that backfires would be the result of a vacuum leak, bad timing, or a worn carb, not a faulty pump... My carb is barely 6 months old and I just thoroughly cleaned it. I just replaced the intake gaskets, and I did so very carefully according to Edelbrock's instructions. I just replaced the distributor, coil and plugs, and my electronic ignition is firing strong at 8-degrees BTDC. All I have left to replace is the fuel pump and carb. You can imagine what I'm hoping is bad.