Changes by last author:
Changed:
| Reverted to old version to remove comments about a tuning procedure that use closed loop, it deserve a tuning guide of it's own as there are minor differencies that make it hard to describe in the same page. I'll try to write one for that procedure too ASAP. -JK |
| Check TuningSession/VEtuning for notes related to the improved procedure, closed loop tuning |
| It's very important to understand that any WBo2 readings taken when the engine has missfires, bogs or just acting strangely is unlikely to be correct. For example a missfire reads lean! because the sensor only measures burned petrol, liquid petrol is ignored and only the air will be measured. Under conditions like this you need to read the plugs to get it right. |
| It's very important to understand that any WBo2 readings taken when the engine has missfires, bogs or just acting strangely is unlikely to be correct. For example a missfire reads lean (no matter how much fuel is injected) ! because the sensor only measures burned petrol, liquid petrol is ignored and only the air will be measured. Under conditions like this you need to read the plugs to get it right. |
|
I also suggest that you disable closed loop lambda control: Settings->EGO(Lambda) control. Set Lean limit(%) and Rich Limit(%) to 0. If you don't you will have to review the ego correction field in the logs too after each session.
We start with the extremely low load sites. Start off by letting the car idle, now tune the VE at the loadsite the engine use until the actual Lambda is the same as the target lambda (the value in the Lambda table under Settings-> Lambda table). No need to be anal about this, within 0.02-0.03 is good for now. You will probably need to blipp the trottle a few times to clear up the engine when doing this, expecially when going from a pig rich base tune. |
|
I also suggest that you disable closed loop lambda control: Settings->EGO(Lambda) control. Set Lean limit(%) and Rich Limit(%) to close to 0 (eg. 0.5%). This way the authority range is very narrow, you have total control, but you see immediately which direction to change. With a higher ego_lean_limit (usually 10..20%) the advantage is that you see in advance when you're approaching the desired VE (not just at the last moment, when you go leaner than you liked). In any case, you are recommended to review logs, but with EGO correction=0% you have to look up the desired lambda for every loadsite (and compare with actual lambda, and calculate the necessary correction), while with non-0 ego-correction the controller does the lookup and calculation and you can judge the situation immediately by looking at the ego-correction.
We start with the extremely low(-power) load sites. Start off by letting the car idle, now tune the VE at the loadsite the engine use until the actual Lambda is the same as the target lambda (the value in the Lambda table under Settings-> Lambda table). No need to be anal about this, within 0.02-0.03 is good for now. You will probably need to blipp the throttle a few times to clear up the engine when doing this, especially when going from a pig rich base tune. |
| Now increase the rpm somewhat, 2k or so is fine. Do the same here, tune VE until the actual AFR is the same as the target. Same 0.02-0.03 applies here. Continue doing 3k in the same way. |
| Now increase the RPM somewhat, 2k or so is fine. Do the same here, tune VE until the actual AFR is the same as the target. Same 0.02-0.03 applies here. Continue doing 3k in the same way. |