A couple ECU theories, & a way to get into OL faster

[dougefresh_]

After pouring over many logs trying to figure out and solve some minor 'issues' I saw with my own logs, I came up with a couple of theories that help explain:

1. Why AFR's sometimes fluctuate (off their OL/WOT fuel targets) post shift during WOT, and
2. I figured out a way (that works) to get into OL one row before your FT's zero, and have a theory that imho supports the idea. It also makes for a smoother transition into OL/WOT.

The word doc runs you through #1, which isn't as important since there isn't anything that can be done about it. It's just a theory, and it may be wrong. The word doc also describes #2, and then the excel file includes my theory on why this worked based on comparing stock vs. OTS fuel tables, and includes some logs showing the results.

Again, these are just my ideas, and I could be off here, but it makes sense to me I welcome any criticism, thoughts, ideas, etc... I would have had more data, by my AP died last night after taking like 5 great WOT runs.

Enjoy!!

EDIT: Slight edits to word doc for clarity.
ALSO: Smoker6 was instrumental in figuring out the OL/Part Throttle changes. Thanks Bro

 

[FORZDA 1]

After pouring over many logs trying to figure out and solve some minor 'issues' I saw with my own logs, I came up with a couple of theories that help explain:

1. Why AFR's sometimes fluctuate (off their OL/WOT fuel targets) post shift during WOT, and
2. I figured out a way (that works) to get into OL one row before your FT's zero, and have a theory that imho supports the idea. It also makes for a smoother transition into OL/WOT.

The word doc runs you through #1, which isn't as important since there isn't anything that can be done about it. It's just a theory, and it may be wrong. The word doc also describes #2, and then the excel file includes my theory on why this worked based on comparing stock vs. OTS fuel tables, and includes some logs showing the results.

Again, these are just my ideas, and I could be off here, but it makes sense to me I welcome any criticism, thoughts, ideas, etc... I would have had more data, by my AP died last night after taking like 5 great WOT runs.

Enjoy!!

EDIT: Slight edits to word doc for clarity.
ALSO: Smoker6 was instrumental in figuring out the OL/Part Throttle changes. Thanks Bro

Hi Douge! I don't necessarily buy into your OL/CL Part/WOT HEGO theory deal. Well, let me say that in CL, the ECU SHOULD use the HEGO only for fueling corrections based on CL Fuel table target values. In OL, the ECU SHOULD ingore the HEGO and it does as far as I can tell from my logs.

The issue you're looking into IMO, occurs due to an error or unstable bit of firmware code in the ECU, not something that is actually programmed. As we have learned very well, the ECU has a somewhat complex algorithm to decide when to enter OL and this is where I THINK the problem is. "Occasionally", the ECU will get hung up in the transition when we do a lift-throttle shift as the ECU must cycle through several OL/CL switches to get back into WOT OL.

 

[dougefresh_]

Hi Douge! I don't necessarily buy into your OL/CL Part/WOT HEGO theory deal. Well, let me say that in CL, the ECU SHOULD use the HEGO only for fueling corrections based on CL Fuel table target values. In OL, the ECU SHOULD ingore the HEGO and it does as far as I can tell from my logs.

The issue you're looking into IMO, occurs due to an error or unstable bit of firmware code in the ECU, not something that is actually programmed. As we have learned very well, the ECU has a somewhat complex algorithm to decide when to enter OL and this is where I THINK the problem is. "Occasionally", the ECU will get hung up in the transition when we do a lift-throttle shift as the ECU must cycle through several OL/CL switches to get back into WOT OL.

Yeah, I predicated page 1 with "If this holds true into OL/Part throttle and OL/WOT." It sucks if it doesn't because this would have explained a helluva lot. Hmmm... I'm gonna see if I can get a call into a good tuner next week to rule out the HEGO functioning under OL/Part, OL/WOT just to be sure And to see if I can sniff out some insights into the CL/OL transition business. Thanks for the input!

P.S. At least page 2 still holds true for sure, and I look forward to your input as to the logic I applied to explain why it works. Rock on my brother!