B9021 access and refinement

[megadeus]

Hi guys,

I've fixed my P1518/P1514 issues from another thread but I want to start this thread for the sake of b9021.

I've searched this forum and read about the .cax files that are suggested. Every application I've seen suggested has been applied to <2002 MY PCM's. I have a 2003 pcm currently running COS 3150003. Am I missing an obvious or obscure selection from this COS to manipulate B9021.

In another thread, I read about B9021 being applied across all COS after? Is this true?

I have read some references that B4003 or B4004 was actually the B9021 table in disguise.

Like many that have stumbled along before me with the struggles of getting the idle PW below 2.2ms at close throttle. I know that the transitional table has a lot to do with adding to that PW output.

If you look at my log, when I hold rpms at 2000, the PW goes below 2 ms and the engine actually sounds pretty good at that point. I have pretty bad plug fouling right now with a rough idle and my wideband AFR is indicating about 11.5~12. (no i haven't hooked it up to the flashscan yet.

I'm a high school autoshop teacher and this project has been an interesting one to share with my kids as they see the improvements with each little change. I keep telling them that you should only do one change at a time to see if that change actually did any good or not. Your feedback to me is also helping the kids in my labs as I share this learning experience with all of them.

Thanks again - Jason

See attached tun and logs:Log_0031.efiLog_0032.efiLS1 _ COS3150003v4_fuelPSIADJ_lambda1_STFTon_0002.ctz

[joecar]

Hi Jason,

See this thread for all the known B9021 cax files: need-B9021-for-01250003

take note: each COS has a base OEM OS, meaning that you can rename the OEM OS to the COS's id.

( each OS has B9021 at a different address; someone had to reverse engineer a PCM binary image to discover where B9021 is located at in the OS for that PCM )

...

I have read some references that B4003 or B4004 was actually the B9021 table in disguise.

...

This is not necessarily true, altho the effect may be the same (now you've got me thinking, I'll have to research this out).


Hey, good job with the autoshop class, and good advice (one change at a time)

[5.7ute]

B4003, B4004 are a completely different parameter, but will have a similar result if set higher than B9021. For instance, if the B4003 minimum pulsewidth value is hit, the value in B4004 will be used in the fuelling calculation. This is why these parameters must be set lower than or equal to B9021.

[joecar]

Hi Jason,

BTW, some miscellaneous comments on your ctz file:
- B3616 (PE Enable): this is too restrictive; set it same as 2002 F-car (12212156).
- B3618 (PE EQR): if you're done tuning (MAF and VE tables are correct), then this may be too rich for NA; for boost it is ok.
- B4001 (IFR): slope is ok for un-referenced FPR; but for boost, it is recommended to swap to referenced FPR (for which IFR will be flat).
- transmission WOT parameters are upside-down (downshift MPH should be below upshift MPH).
- D0960,1,2 (Throttle Kickdown): set these to 100% all across to allow PT tables to control shifts; more info: When-throttle-kickdown-is-not-set-at-100

[joecar]

Also, more general info your students may find useful and/or interesting:
Summary-Notes
Calc-VET-correcting-MAF-and-calculating-VE-(in-single-log)
Calc-MAFT-correcting-VE-and-calculating-MAF-(in-single-log)-->reverse-of-Calc-VET
CALC-VET-Summary-Notes
PE-Mode-Controls-All-Closed-Loop-Fueling

Please feel free to post questions.