AFR flutter

Hi guys,

Im trying to think right now on how to set this up and it has me at a bit of a loss.

The stock engine control unit commands the ecu to flutter above and below stoich at idle and steady state, low load for emissions purposes. is there a way to tune this into a standalone?

The car in particular is a 2jz is300 and I will be wiring a LINK g4+ thunder in to control the engine while I retain the stock ecu for some basic controls.

That's for catalyst oxygen storage capacity. It's not something you would ever need for any emission test outside of government certification.

Can you give us more background on the project and what you are trying to control with each ECU?

If you want the catalyst to work with a narrow band sensor at its best it is necessary to be done like that --> Poor mixture (to oxidize HC and CO) and rich (to reduce NOx) cyclic behaviour.

This function depends on the algorythm which is pre set in the ECU, which means that the ECU you use have it or don't have it. Ampiltude and periode of rich and poor mixture is not symetric. Apexi PFC i am using in my everyday car has it for instance.

Google search will give you many information about catalytic converter AFR regulation

The link g4+ can perform the same task in either Stoich Mode (narrow band) or Stoich Mode (wideband). These modes provide some amount of dither around the target AFr.