1994 Other Mazda Models backfiring

Re: 1994 Mazda MX3 1.8 lt V6-
Starting and backfiring problems-

1. Until recently, the care never started in humid or severely cold conditions. Each plug was receiving a strong spark, the plug wires were good and there was fuel. The engine doesn't burn oil or coolant. Two days ago, I discovered moisture beneath the cap and severe rust between the igniter and coil. I cleaned these as best I could (w/dremmel wire brush) and replaced the heavily worn and cracked gaskets, I replaced the cap and rotor and reassembled it and it starts in any weather. I solved the starting problem, but another problem persists.
2. When the engine reaches operating temperature, it begins to backfire and stall below 2200 rpm. If I feather the throttle in 1st gear using the shift " hold" button (automatic tranny) and coax the engine above 2200 rpm then it runs, but below 2200 rpm it backfires and stalls. During highway driving, I cannot accerate above 4,000 rpm without the same problem occuring.
This problem never shows itself when the engine is cold.

Thanks in advance,
Marc