have changed spark plugs, fuel regulator changed rotor and cap distributor
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1991 Ford F-150 Question: backfiring through intake, rough idoling, burning rich what do you think
Answer #1G. T. Service Center (4234 Answers) , Stephenville, TX - (254) 638-3236ProfessorG March 20, 2014, 13:34Master
Did you check the timing or do the compression test. Looks like you just changed parts, those things are mentioned for possibilities, nothing about changing on a guess. If it is backfiring, it would suggest the timing is off, but a compression test would tell if it might be a timing chain, or if ignition timing is off it could cause the same issue. Then these had problems with the stator's and ignition modules, but it should be tested unless you have more money then I do, and I don't have much.
Answer #2RayRedhawk April 26, 2014, 16:19Rookie
Sounds like your fuel/air ratio is running a little rich. You may want to also change out the EGR and PVC valves.