94 silverad 5.7L backfiring through tbi only when hot
 

I currently have a problem with my truck backfiring through the tbi when hot only. when cold it idles perfectly and i have power to boot. but when heats up to temp the engine struggles and backfires when under load going on a flat road or up a hill. Replaced both temp sensors plug wires cap button plugs fuel filter air filter map aic and replaced all vaccum hoses and pcv valve. any help greatly appreciated

Take a very close look at the Distributor Cap, it may be cracked.

nope that want it replaced cap and still the same