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Ignition/Tuner/ECM/Fuel InjectionNeed advice on ignition issues? Questions about a tuner? Have questions about a EFI calibration or Fuel Injection? Tips on Engine Diagnostics, how to get codes, and what they mean. Find your answers here.
Can anyone explain what is going on in the background of the EFI system that would cause lower injector pulse width on the rear cylinder when the VE is higher than for the front?
Simple math would say Higher VE = Higher Pulse Widths.
Is the EGR effect tables contributing to the calculations or something totally different?
Is the rear cylinder actually getting less fuel to equal correct AFR?
Bike is running good, just trying to understand what is affecting what.
The VEs and NEW VEs are the same so it is either in an open loop situation or the O2s are disabled. I would say to let it warm up and then look at the NEW VE front and rear vs the VE front and rear.
Also, changes to adaptive fuel tables are not shown in the VE - there could be corrections occurring that you are not seeing - again if the O2s are active.
Last edited by Ed Ramberger; Jun 14, 2019 at 07:09 PM.
The VEs and NEW VEs are the same so it is either in an open loop situation or the O2s are disabled. I would say to let it warm up and then look at the NEW VE front and rear vs the VE front and rear.
Also, changes to adaptive fuel tables are not shown in the VE - there could be corrections occurring that you are not seeing - again if the O2s are active.
Ed, thanks for the response.
Yes it is running all open loop. Here's another snapshot with the temp up to 235, doesn't seem to matter what temp.
You are describing an out-of-tune condition. Since it’s open loop the system virtually runs from whatever the calibration has for values, NOT tailored to your bike.
The most important aspect of tuning is to get the VEs calibrated to actual airflow.
Once this has been accomplished expected change results can be relied upon. Anything other than this will never produce the run quality expected.
Either spend the time to learn and use autotune to correct the VEs OR find a qualified, experienced tuner to get the best running bike possible.
Bob
You are describing an out-of-tune condition. Since its open loop the system virtually runs from whatever the calibration has for values, NOT tailored to your bike.
The most important aspect of tuning is to get the VEs calibrated to actual airflow.
Once this has been accomplished expected change results can be relied upon. Anything other than this will never produce the run quality expected.
Either spend the time to learn and use autotune to correct the VEs OR find a qualified, experienced tuner to get the best running bike possible.
Bob
FLTRI17,
Thanks for the feedback.
In this example with AFR, are the VEs still too far out of calibration to consider my original question?
The set AFR is 13.8
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Injector Pulse Width Question
