Have a 33EFI on a mower that runs like a beast for about 30 minutes (give or take depending on how hot it is outside) and then it loses power and then dies. Let is sit 30-60 minutes and it will run again. I've replaces spark plugs, have spark to both cylinders and have pulled both injectors and watched them squirt. I bought one new coil and have tried it on both sides but still the same issue. I have also swapped out the O2 sensor with a different one. Exact same issue. Any other ideas?