I've got a 335 with the Kawasaki engine in it.
When started, it runs fine at low idle but when you bring it to fast idle quickly it pops & back fires.
When you bring it up to fast idle slowly there are no pops or back fire.
I engage the pto and the mower starts to die out until you disengage the pto then it catches back up and stays running.
I have spark at both cylinders, I just went through the carb.
Could this be an electrical issue or a fuel issue?