My short trim over compensating in closed loop?

[0piston]

When posting a KPro problem with your vehicle, please include:
- serial number of your K-Pro
04711
- KManager version (not 'the latest')
1.3.6.0
- the calibration (as an attachment)
- a datalog of a problem (as an attachment)
both attached
- what sort of vehicle you have
S2000
- what sort of ECU you are using
K-Pro
- anything about the car which has been modified from stock which may affect the ECU (don't include what sort of rims you have nor stereo etc).
input is from a 0-1V narrowband output from my wideband
- a specific description of the problem
When at cruise/low load the A/F s.trim is adding too much fuel.. it almost seems like the response is lagging or toomuch fuel compensation. So in closed loop when its trying to achieve 14.7 it is not steady, and is always adding more fuel than needed to achieve its 14.7 target, jumping from a wide range of 14.1-15.1

Also I notice that even though options>settings>lambda overlay closed loop activates at minimum 2%TPS, I still notice it taking out fuel at idle at 0%TPS, is that normal? [/b]

[Spunkster]

What type of wideband are you using? Have you tried just using the stock o2 sensor?

[sinistrs2k]

I beleive the lambda overlay feature you are looking at is for the values displayed on the table showing what fuel corrections you would need to make in order to achieve the target lambda value. I don't think it affects when short term corrections are actually made.

For example, if you switch the table view to the lambda overlay option, it will only populate the table when the TPS is at 2% or greater and ignore AF values when you let off the throttle (it goes below 2%). You would want to set it higher so it doesnt read erroneous values when you let off the throttle after a pull.

This is how I think it works anyway, please correct me if I'm mistaken.

J

[0piston]

What type of wideband are you using? Have you tried just using the stock o2 sensor?

PLX, unfortunately the stock one is not working.

[0piston]

I beleive the lambda overlay feature you are looking at is for the values displayed on the table showing what fuel corrections you would need to make in order to achieve the target lambda value. I don't think it affects when short term corrections are actually made.

For example, if you switch the table view to the lambda overlay option, it will only populate the table when the TPS is at 2% or greater and ignore AF values when you let off the throttle (it goes below 2%). You would want to set it higher so it doesnt read erroneous values when you let off the throttle after a pull.

This is how I think it works anyway, please correct me if I'm mistaken.

J

Thanks for the clarification J!

[Spunkster]

In closed loop it will never hold a steady AF reading. It always fluctuates, this is totally normal and does this with the stock sensor as well.