AEM FIC Tuning

[Focus_Sh1ft]

i found a function in the fic to switch the o2 map to be switchable with boost pressure. now just need to test drive to see how well it works!
it worked sitting in the parking lot, i was able to drop it down to 12.2 at idle.

I'm jealous lol. That's exactly what I wanted to do but could never get the O2 skew to work correctly.

Right. Yet. You're definitely shortening the life of the motor.

If that weren't so, Toyota would run the motor at that AFR too, and so would everyone else.

Definitely in agreement here, and was going to richen the entire map when the weather warmed up.

I always thought low 15 was safe because in closed loop the mixture would generally run on the leaner side of stoich, and go as lean as 15.4ish frequently. I probably should just be playing it safe rather than trying to squeeze out as much fuel economy as possible...

[Bluevitz-rs]

Originally Posted by Focus_Sh1ft

I'm jealous lol. That's exactly what I wanted to do but could never get the O2 skew to work correctly.



Definitely in agreement here, and was going to richen the entire map when the weather warmed up.

I always thought low 15 was safe because in closed loop the mixture would generally run on the leaner side of stoich, and go as lean as 15.4ish frequently. I probably should just be playing it safe rather than trying to squeeze out as much fuel economy as possible...

This is what I was saying about the difference between the Yaris ECU and the Echo ECU. The Echo's is way more forgiving if it doesn't see normal values. The Yaris will freak out and correct them.

[Focus_Sh1ft]

Originally Posted by Bluevitz-rs

This is what I was saying about the difference between the Yaris ECU and the Echo ECU. The Echo's is way more forgiving if it doesn't see normal values. The Yaris will freak out and correct them.

I'm just curious as to why you think this? Theoretically, if you're manipulating the AFR sensor's voltage, it can't really correct itself since it's the main method of fueling feedback (and therefore will think that everything is okay).

However, I definitely think the ECU might see continuous low voltage at the AFR sensor and throw a code. More importantly though, it probably would throw the engine into open loop. No one has really tested this method of tuning on the Yaris yet, so I'm just speculating.

Could this be where the Yaris and Echo ECUs differ?