[96wWindstar180K]

Ed_Strong
The backfiring sounds like a timing issue as the timing is controlled by the pcm that confuses things more. However as Wiswin said that a fuel delivery problem could be an issue as Im well aware of. I had kept checking my fuel pressure (purchased a fuel pressure gauge from Sears for $30.00) There seemed to be no problems. However I realized by leaving the gauge on as driving (cowl off taped guage to the windshield I could watch the pressure change. The biggest note was at cranking. When you first turn the key on you hear the fuel pump run for a second or 2. I thought that was good. When I applied the gauge the fuel pressure was 20 Llbs. If I turned the key off and then back on the fuel pump would run again and the pressure would go to 30lbs. The fuel pressure should remain about 40lbs with the key on engine off and maintain that pressure give or take. If you notice change at the given rpm of the backfire I would suspect the fuel pump or fuel regulator. My problem was similar in that I figured if the fuel pump was bad it would starve at higher rpm. Not so. I you cant figure it out in my opinion I would take it to a shop and have them diagnose it. It cost me $108. to put in on the computer and tell me exactley what was wrong. I had them do the fuel pump but i replaced all the fuel injectors as one was bad and I had so many miles. I kept throwing money at it replacing parts and could have had it diagnosed for much less. The only reason I didnt feel to bad is the age of the van and miles. Replace it now or replace it later. Preventative repairs