2005 Precedent sputtering and backfiring

[bwillis]

I have a 2005 Precedent with the FE350 engine. My cart has always taken a little while to "rev up" before it would finally take off. I replaced the belts and that seemed to help a little bit. There has also always been a backfire from time to time on deceleration.

The latest issue has me stumped. When cold, I can get it to rev up and take off and drive fine for a few minutes, it then begins to sputter and backfire and barely move. When I let off the gas and try to start back up again, it will backfire, pop and then finally start sputtering along again to get it back in the garage. While it's sputtering along, every now and again it will start running fine and then right back to sputtering along.

I will note the spark plug is dry and also covered in soot. We tested the spark and it is orange. It also will jump past the diode to the engine block when we test for spark.

So far, we have done the following (based on reading other threads):
-Cleaned the carb
-Replaced spark plug
-Replaced fuel filter
-Removed and cleaned fuel tank
-Cleaned fuel pump (the fuel pump seems to pump as expected, I've removed the tube going into the carb and it spews fuel out)
-Disconnected rev limiter ground

My father in law thinks it is the ignition coil providing a weak spark, but I don't want to get into replacing that unless I know for sure that's the issue and I've exhausted other options.

The cart has 1089 hours on it, 12 of which are mine...which is why I'm extremely frustrated! Any help you can provide would be greatly appreciated.

[Golf cart guy]

Chances are good its coil

[Capt.Jack]

could be the coil but the black soot plug doesn't line up with the coil being bad. Sounds like its running rich which would cause back firing and running poor and a sooty plug. I know u replaced the carb but check the clear breather hose going to the carb make sure its not clogged. I have had this happen to me.

[bwillis]

Originally Posted by Capt.Jack

could be the coil but the black soot plug doesn't line up with the coil being bad. Sounds like its running rich which would cause back firing and running poor and a sooty plug. I know u replaced the carb but check the clear breather hose going to the carb make sure its not clogged. I have had this happen to me.

What led us to believe the coil was basically that it wasn't burning a fire hot enough to burn off the fuel. Of course the orange flame didn't hurt our thought process either. Before I tear into this ignition, I'll go ahead and tear the carb off again and make sure it's clear as well as the hoses leading to the carb. It being something simple would be such a lifesaver as far as time, effort and money are concerned. I'll keep you posted.

[kcc865]

Any word on what fixed it?

[Golf cart guy]

Originally Posted by kcc865

Any word on what fixed it?

My guess is still the coil. So rare for it to be a carb issue. The spark plug being black is another good sign it was coil too.

RPM limiter would be my second guess

[bwillis]

So just an update. After the coil, it was not turning over enough to actually fire, so I broke down and took it to the shop. $700 and 2 months later, they pulled the engine and found out the flywheel was coated in mud, which was not allowing it to spin very well, thus causing issues. This was more than likely an issue when I bought it, as its sat in the garage since that time and was only driven 10 hours, if that, and only on the gravel driveway.