2003 Ford Windstar - Battery Light

Car drives good at times,thought it to be bad gas,but sometimes acts like it’s not getting compression, gauges go haywire, engine light and battery light comes on. It even back fired yesterday almost didn’t get in home. Shop has cost lots, did fine till they put new a/c on and now same problem exist again, worse than ever. It is parked now.

The problems may be caused by a failing body control module.