lakeffect2

I have done Three wideband VE learns with the EBL programming. I don't like the results. They seem way off

Al three times in instances where I would least want fuel, like it's already rich into the 11-13', it wants to add gross amounts of fuel. the indication on the VE learn difference screen show values of +8 to 14. It's not cutting fuel, it's adding.

In other situations, I see the yellow box (not learning) not the green box. This is at a point under light throttle, or off the gas for several seconds (like anticipating a traffic signal change down the street) These areas also go super rich at lower Kpa values (30-400 and higher vacuum gauge readings (16-18)I understand "Give it want it wants", but it doesn't to be pig rich when coasting to a light either..


I understand that HighwayMmode needs to be off, but is AE, DE and DFCO events preventing the learn process to produce false or no learn conditions?

Thanks in advance for your time to answer.

Dave Buchholz

RBob

iTrader: (1)

Open loop decel option is set, that will prevent a NB BLM based VE Learn when near to or off the throttle.

Option Word 1 - Bit 1 - OpDcl

Once that area is learned in the engine may start surging. If so re-enable open loop decel and add a little back into the VE table. Due to the low air density in the intake during decel having it a little on the rich side is better.

That helps prevent surging and misfires.

As for the VE Learn adding fuel when you think it should be removing it, it just goes by the NB O2 sensor feedback when in closed loop BLM learn mode.

RBob.

lakeffect2

Thanks RBob As to that last point, if I stay in wide band VE learn, what areas typically are learned better by WB than NB and vice versa? Under certain circumstances, does one have advantage in areas that the other doesn't.

One would think WB to be "always" better.

Dave

RBob

iTrader: (1)

Once the VE is close a WB lean is better. As it is faster and will learn in open loop areas (decel and WOT). When starting out a NB BLM based learn is better as the ECM will adjust fueling real time. Makes it easier to drive the vehicle for the initial learns.

RBob.

lakeffect2

Thanks, I tried to ask in a generic way so others could benefit from geheral knowledge of the EBL system. The orignal EBL thread is so long now that it defies usefulness. Maybe there could/should be a Frequently Asked Questions area that would provide a base of simple answers to general questions about EBL usage.