My brother has a 2001 Honda Rubicon that backfires after going fast. For example, after going 45mph and completely letting of the throttle the exhaust seems to sputter a few times, then it lets out one loud pop around 30mph.

I've already tried adjusting the pilot screw from it's factory default setting of 2 3/4 turns to 1 3/4 turns, 3 1/4, and 3 3/4 turns without any improvement. It also does this in push button or auto shifting mode if it matters. The air filter has been cleaned and oiled properly, engine oil has been changed, and the idle speed it set correctly. Top speed, power, and engine braking also seem to be fine. FYI...everything is stock...no aftermarket parts or modifications. It also has 1060 miles on it and has been backfiring for a couple of years.

Any help or advice would be greatly appreciated.

Thanks!

 

sidewinder, my old foreman does that too. i just dont let off the throttle, i just ease up lighty. i can't help you toher than that.

 

do you have the baffle out of your exhaust. if so that will make it back fire