I seem to have a tuning issue with my Power Commander with Autotune. The front cylinder seems to be running lean and the trim tabs on the PCV software are in the -20s and -30 around 2K-3K RPMs at 10-40% throttle after I go for a quick ride. The rear cylinder is running good and there is very little change to the base map. Both cylinders are using the same base map numbers. I know one cylinder usually runs hotter, but for that much of change to happen? Plus the front cylinder is misfiring in that range and backfiring a lot. The bike runs goods below this range and idles fine. If I disconnect the autotuner, cylinder fires and bike runs. I checked the front header bolts and they are on tight. Any ideas would be greatly appreciated. It's not a mechanical issue. Seems to be a tuning AFR issue.

 

Seems you found it already by disconnecting the tuner......bad tuner.

 

It shouldn't be...it's brand new! I just decided this week to put it on after going all year without it. I had the old style tuner with the two units from PC. It went bad last fall and PC replaced it under warranty at no charge. Got the new single tuner they make now, new o2 sensors and wires. I replaced the sensors and tuner, but not the wires. The reason for the warranty issue was a sensor went bad. I have new sensors on so maybe I should install the new wires too.

 

I know it's new, but it's bad. Where did you buy it from? If you bought it from FM call him and get it replaced. Once you put a diff one in, them report back either way.....

 

Adjusting by 20 or 30 at a time is to much, you should set it to 5 or 10 max and ride for longer distances and set it not to start until the bike gets warm. That 30 might be coming from the first 30 seconds the bike is running, you can't go by that. In any case 30 is too much trim at one time.

 

Yesterday morning before I went out on a poker run, I attempted to get the autotuner working one more time. I had replaced the sensors and the AT unit they sent me under warranty, but not the cables. The cables between the sensors and the tuner looked fine and were connected properly. I still went ahead and replaced the wires so I have all new equipment installed. Buttoned the bike up and took it for a spin. Low and behold, the bike ran like a top. I went back home, plugged in the laptop and checked the trim levels. A few changes here and there, but nothing like -20 or -30. Also, the more important part...no cylinder issues or exhaust pops. I ran the bike all day yesterday for nearly 200 miles and she ran like a raped ape!