I've recently made the jump to Ethanol (~E70) and am trying to run open loop in cruise to lean out the AFR's to high 16's/low 17's and set timing in the high 30's/low 40's.

After leaning out the cruise areas of the map pretty heavily, the AFR's logging on the wideband are still way richer than I'd expect and not changing much as I go leaner on the fuel map. E.g. AFRMAP is 17.1, but wideband is still showing mid-high 15's

Here's my cruise log. Note the AFRMAP vs Wideband.


And here's my OL settings and scaling/latency. Injectors are FIC 1050's.


Do I just need to keep pushing it leaner on the fuel map, or have I stuffed up an OL setting or latency? I've had this all working well on another car I tuned using the same settings I thought...

 

Keep doing what you're doing. The values in the fuel map are arbitrary numbers and don't necessarily correspond to the real AFR you'll get.

 

Thanks Raptord. Just wanted to make sure I wasn't doing anything silly as another Evo 7 with same injectors/scaling/latency and very similar mods only needed mid 16's in the fuel map to achieve 17.0 at cruise, so I was a bit worried.

Will lean it out some more and report back if it makes no difference

 

Just realised part of the problem. It's his first tank of ethanol, so had a little bit of pump 93 in the tank when he first filled.

He just filled his 2nd tank of ethanol and it leaned things out nicely. I've made a small adjustment and it's spot on now. All good