Miss under load first thing i would suspect is plugs and wires.

Answered by saturntech9 (expert)
23,192 answers provided

Im thinking camshaft. Plugs,wires, rotor have been replaced and distributor cap

Response from Baines48
1 question asked

If it only misses under excelleration i wouldnt suspect a cam shaft that should effect at all different rpms.Usually when it happens under excelleration its a igniton issue.Is it worse with the ac on?Also how about your coil?

Answered by saturntech9 (expert)
23,192 answers provided

The truck backfires through throttle body (TBI) when under load. Don't know what to check next?? Cam etc...

Response from Baines48
1 question asked

Have you checked the ignition timing yet?

Answered by saturntech9 (expert)
23,192 answers provided