My 1989 Southwind 454 P30 chassis with 48,000 miles on it started popping back at the carb. I had a hard time figuring out if it was fuel, (vapor lock) or ignition. I searched all the internet for days trying to figure this out and ended up more confused than before. I changed the rotor, the distributor cap, the ignition module, the wires, fuel pump, all the fuel filters and the plugs, it effected nothing, the popping was worse than ever. I still couldn't separate it from fuel or ignition. I even contemplated pulling the fuel tank when I finally figured out it had a internal fuel pump to supply the mechanical pump. I changed the fuel pressure regulator diaphragm (A Holley kit #12-807)and made sure the tank pump was working, still no help. I then realized it was popping before it got hot so I thought that might eliminate the fuel vapor lock issue. The last thing left to check before buying a new distributor was the coil. I took off the cap and removed the coil cover and the screws holding the coil. The old distributor cap was black, the new Borg Warner select was grey. Inside the coil area where the coil sits in a pocket in the HEI distributor was black with carbon, I had a ah-ha moment--- the coil was bad and arcing through the plastic to some of the plug terminals causing the backfire through the carb. Some of the other things that were mentioned on the internet were, accelerator pump, burnt valves, a vacuum leak and a quadrajet rebuild.
It was a bad #4 plug wire that caused the coil to arc inside the cap. High voltage HEI WILL find a place to put that arc.
2000 F53 Southwind 32v
