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simple fuel controller

dynajohn

New member
Three years ago when I bought my 2015 K1300s I bought a simple fuel controller which helped with some issues. As I remember this device altered the signal from the ambient air sensor. It had some adjustment. I sold it when I got the ECU re-flashed and the literature that came with it. Anybody know what this was and if they are still sold?? There were others here that also used this. I simply can't remember where it came from. I think they were also used on the K1600's.
 
Sounds like you may be referring to the Booster Plug, which plugs in between the ambient air sensor and the wiring harness and adjusts the ambient air signal downward to slightly richen the mixture, or the AF-Xied controller, which actually works with the ECU and is adjustable as to how much the mixture is changed. The Booster Plug is generally considered a less desirable way to go—while less expensive, the ECU over time compensates for the temp adjustment and largely negates the effect of the Booster Plug. The AF-Xied is more $$, actually works with the ECU and is reported here in the forums to be effective, and is supported here in the forums by a developer.

HTH,
DeVern
 
Are you referring to the $60 BoosterPlug?
It is/was a simple resistor in line with the airbox inlet temperature probe.
It “fooled” the ECU (for a while) into running a bit richer to compensate for what it sensed was cooler air.

FWIW, later experimenting with BMW bikes showed some evidence the ECU was smart enough to compensate after a number of open loop/closed loop cycles to nullify the BoosterPlug change.

You can make your own by inserting a certain value resistor in line with the temp sensor but the BoosterPlug makes it very easy by providing connectors so no wire cutting is needed.
 
The AF-XIED is a little more complicated in that it fools the ecu into thinking it’s running lean by changing the O2 sensor feedback voltage. Again, it’s basically just 3 resistors in a voltage divider network with easy to install connectors so no wire cutting is needed. In this case the ecu never knows it is being fooled but because the O2 sensor is narrow band it is limited to the amount of change allowed.

I put a BoosterPlug on a 1200gs and an af-xied on a 700gs. The 700 seems to vibrate less with the device although i have no idea why this would be so.
 
Thanks the one I had was the AF-XIED. It had some adjustment (a dial as I remember for the amount of offset). It did work but I wonder if the booster plug works better. The booster plug uses a 2nd ambient sensor to offset the fuel map when the ECU goes open loop (anytime you are accelerating or not operating at a steady throttle setting). Reason I am asking is I have a fiend who is looking for one of these simple inexpensive devices to help with a fueling issue. Anybody use one or both at some time to help with a fueling issue. My 2015 K1300s didn't really have any issue I just used the AF-XIED to richen the mixture to compensate for a air filter change and a slip on muffler.
 
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