2018 Yaris SE 5MT - T-Sport w/Valvematic!

[ArmstrongRacing]

Originally Posted by atomic_hoji

At least if I'm wrong the problem had us both duped?!

Here's a plot from when I had Techstream running on the weekend.. The Fuel Pump duty request was only about 75% (scale labels are goofy) most of the time - only jumped up to about 90% when I jumped on the throttle some. STFT is all over the place, not surprisingly, but does average out to around 0%'ish... sort of... LTFT (not shown, doesn't change much like STFT) was still -30%, but did jump up and down some. Used a reset Utility to clear all the learned values; even though I had the battery disconnected while I was doing wiring repair, the LTFT was still way off. I'm sure a bad learned value isn't helping the cause.

Attachment 59635
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-- Adam

The graphs look somewhat normal to me. The only thing that looks strange is at the end where you start stabbing the throttle. It’s proving feedback on the first stab but then it just starts reading a full rich condition. That tells me either it went into Open Loop or you A/F sensor is not reading properly???

[atomic_hoji]

Originally Posted by ArmstrongRacing

The graphs look somewhat normal to me. The only thing that looks strange is at the end where you start stabbing the throttle. It’s proving feedback on the first stab but then it just starts reading a full rich condition. That tells me either it went into Open Loop or you A/F sensor is not reading properly???

That's good to know, thanks. Getting into fuel trims and some (most) of this stuff is new ground for me, so nice to know what's normal.

Unfortunately I don't recall what I was doing when I did the run, though looks like accelerating and shifting under mid-throttle - seems about right..? I have checked the AFR resistance and it was in spec, but ya maybe the AFR is mis-behaving or something related is tripping the ECM up and going open loop. Going to try some more troubleshooting once I have the FPC ECU installed - which is on order and was able to pick-up a 2000 mile unit off eBay for about half the price.

-- Adam