98 Astro WOT Backfire issue.

[Rajon]

Hi, first time posting. I request the wisdom of "Blue Bowtie" or anyone else.

I have a 98 Astro 137k Miles VIN "W". When you give it wide open throttle, engine sort of hesitates. When you slowly give it some throttle, accelerates good. Also just got a P0101 MAF code.

Changed Distributor cap, rotor (AC Delco) and wires (Aftermarket). I checked the ignition coil with my DMM accord to AllData. When I checked for ground on the bracket, my DMM would'nt beep. Im wondering if this could be the problem. The coil seems difficult to remove. During the winter when the temperature first went below freezing, the engine would'nt start. Would crank but not start.

Im guessing your going to tell me to check fuel pressure so I'll buy a tester tomorrow.

Please reply. Thanks!