I have a 20 hp intek briggs and after I run it for about 10 minutes it will start to backfire and sputter it will do this for a couple of minutes and then it will run fine for a few minutes and then back to sputtering. Any help would be appreciated.

sounds like you have trash in the carb or water. or an obstruction or pinch in the fuel line.check your tank,line,fuel filter , the whole fuel system :wave:

Yes I agree with jabbird. DO you haev a hard time starting it? Did this ever sit for alot of time? Old gas?Is this on a tractor or something? Ifit is, does it sputter when accelerating?

this is on a john deere L118 I bought it new in 2004. never sat for a long time, and put sta-bil in it for the winter. yes sometimes hard to start. no trouble acelerating

take out the plug, is it wet? if it is then it may be flooding

Several things come to mind, but I would check the engine ground and carburetor ground and make sure the fuel solenoid on the carburetor is working good. Check for possible water in the fuel and possibly the ignition module may be causing your problem.