Mowerman78

Has two tanks but front has been disconnected for years.and I only have the in tank pump.also I removed the cat and that's not the problem.

Mowerman78

So I've ruled out the FP.and the cat is OK.unplugged the o2 and it ran worse.idk what is causing this but it seems like its only running on three or four cylinders.I'm so confused.it starts too easy to be timing I would think.guess its time for a compression test?!

fltdriver

While you are doing the comp test check each plug for fouling.

Mowerman78

What will that tell me?

fltdriver

It could tell you a few different things, the most important being if the plug is fouled but comp test is good for that cylinder than you have an issue delivering spark from the coil to the plug (bad wire for that cylinder).