I have a 1997 Yamaha G16 gas golf cart that's not running properly. I replaced the carburetor and then it tries to start but begins to backfire through the new carburetor. I can remove the spark plug and close the gap, reinstall the plug, and it will start but not accelerate. I can then remove the plug, open the gap back up to spec, and it will start then begin backfiring again and not run. JN6-113598 is the number on the frame. So far it has a new, aftermarket, carburetor, new Spark Plug, BPR2ES, new fuel pump. I have replaced all hoses, there was a small pinhole in the original pickup tube in the fuel tank. Any help would be appreciated.