My 2012 trx420fm fuel injection has always had the well known backfiring during deceleration. Recently it has started to misfire/backfire badly when applying any throttle in nuetral. It will stall if one attempts to ride. Latest sympton is it would turnover but not start.
Verified the following:
Fuel pump works
Fuel injector replaced a few years ago
Have spark
Noticed when pulling plug, it was wet with fuel, and very black with carbon.
Cleaned plug and it started but backfiring and missfiring got worse over a matter of minutes until it stalled. Pulled plug again and it had already started to foul and this occurred over of 10 minutes max.
No way to get troubleshooting codes of trx420fm that im aware. Game plan is to start with fresh non ethanol fuel, rebuild/replace fuel pump/filter assbly, new injector. Ill apply jumper to bypass sensors to determine if those are bad. I know fuel management has been a problem with these but not sure how to procede. Any guidance would be great.
Thanks in advance. Sorry for long post