GMT900 PE and AFR- What the hell?

Why is this?

The before log is stock.

The after log is some minor TM work and tried to lean up PE by setting the EQ ratio to 1.147 across the board.

Why did just changing the EQ ratio affect the commanded AFR ratio all the time? LTFT's also jumped.

It's only been fueled with 91 (best available in this area - can't get 93), so the alcohol stuff shouldn't be coming into play.

Is the gas station I filled up at selling E10 or something as 91 or am I missing something:doh:

Sorry for the long logs.
Thanks,
Brandon

Dud you change any of the PE Enable settings?

Nope, just the EQ ratio for gas.

I meant to post the stock tune for comparison, here it is.

Disable your cat test.

Russ Kemp

Russ

Cat test - Do you mean COT? I know that it's still enabled and set to 1.33, but would that affect the commanded for the whole time? That log's like 30 min long.

Just confused why in the before, it looks exactly like you'd expect it too, then the after acts like it's running E15 or something...

Thanks for the responses.

So, for curiosity, I set the stoich for 0%-50% alcohol to 14.58, logged, and it was commanding 14.58 and the ltft's settled down to about -3%.

So I'm guessing either the two different gas stations I've used are selling something as 91 that isn't 91.

or

Some additive in the gas is throwing off the fuel composition calc's.

or

For some reason this thing can't identify what fuel it has in the tank.

Any other options I'm missing that would explain this?

Thanks,
Brandon