Got the LC-1 with O-meter pluged in the other day. Took a 115 mile round trip today that was mostly wide open road at 65-70 mph. When in lean cruise the O-meter would show anything from 17 up to 18 afr. On the return trip I hooked up the laptop to check out the datalog. At 2200 rpm, 70-80 lv8, 56 SA is where the 17 -18 afr comes in.

I noticed that my BLM's was at 128 so I checked the ALDL flags and found learn control was disabled. Loop status was closed, O2 sensor was ready but no BLM update. When I got home I check everything(that I know of) and can't figue out why learn control is disabled.

BLM min. update temp is 140
BLM max update temp is 230
min. LV8 to update is 50
BLM min update rate is 1.35 sec.
Max allowed is 160
min. allowed is 108

What am I missing?

BTW, 24 mpg with A HSR 383. Just hope I can stay close to that when I"m not running too lean.

 

Target AFR != stoch

Check your Target AFR. Is it equal to stoch or not?

Perhaps you are in hiway mode with a lean target AFR.

 

I'll go check that.

I can see where that could cause the afr to be off but whould that cause the BLM's not to update? Wouldn't the ecm still try to correct the AFR even in lean cruise?

Thanks,
Dewayne

 

This code excerpt is from a $32 mask. $32B and $6E should be similar.

It makes sense to only update the blms for a stochiometric mixture. That's the only mixture point where the narrow-band O2 sensor behavior is meaningful and where a forced oscillation around the operating point by the integrator would make any sense.

At leaner mixtures, the O2 should indicate lean most of the time, so it is not useful for feedback.

************************************
* BL STORE QUAL'S
*
************************************
LDAA L005B ; GET CURRENT COOLANT
CMPA LC5DD ; If Coolant 50c <= Disable BLM update
BLS LED9B ; BR IF COOL GT 50c
; ... else
CMPA LC5DE ; If Coolant >= 140c Disable BLM update
BHI LED9B ; BR IF COOL LT 140c
; ... else
LDX L00CE ; Total AFR Value
CPX LC3CB ; STOCH RATIO
BNE LED9B ; BR IF AFR IS NOT AT STOCH
; ... else
;
; QUAL'S MET, ENABLE BL STORE
;
ORAB #$02 ; SET b1
LDAA L0063 ;
CMPA LC5DF ; 0, Min ld val for BLM
BCC LED9D ;
; ... else
;
; QUAL'S NOT MET, DISABLE BL STORE
;

 

Stoch was at 15.7. Not sure why, I don't remember ever changing it. I have burn a lot of chip to get where I am now but I only make small changes to 1 or 2 things at a time. I hope after today I have the part throttle stuff close enough to live with.

My next days off I plan to work on cold starts. This thing runs like crap till it warms up to 115 or so then is started acting better. Then I'll have to move to WOT, as is when I floor it from a stop I only get 14 to 15 on th LC-1

I'm off for a short test run before I make a 250 round trip to see my son play his last football game of the year.

Thanks for the help.

 

It looks like your in Hwy mode.
You'll have to disable it to tune your cruise area.

Any time the cmd afr isn't = stoich constant, your in some other mode. Either startup or hwy etc. The fact that your blm is 128 makes me curious though.
There's a max time in HM qual. If it's set to 128d it takes around 30 minutes for it to time out. A setting of 60d will take around 10 minutes. I've never timed it exactly or calc'd it from a log. I just watch cafr on the dash in TP.
It either equals the stoich constant or my HM afr table. There's also a HM afr delay qual. It's set to around 10d. My xdf doesn't do any scaling to those quals. It just displays them as integers. How these two work goes like this. While in HM. The max time setting times out. Learn gets enabled and the delay starts counting. During this time the blm will update as long as the cmd'd afr is = to stoich constant. Once the delay times out you go back to HM and the max time starts counting again. - rinse & repeat-

Cold start- 6E is set up leaner than 32b IIRC. Have a look at the tables for both. When going to bigger injectors you have to scale the s/u pw tables back to compensate. They are a straight pw table and don't get adjusted for inj size in the code. So it's table value x old inj/new inj to start fixing it. Assuming that new is > old. This is kind of buried up in the stickies I think.

Also, the startup SA used is the last column in the rpm vs lv8 table + the SA vs CTS table + a few tables/constants. Theres a post on that but not in the stickies. The stock qual to start using the whole table is set to about 112f.

Now if only I can get my HM SA to work..... I only get 21-22 mpg Hwy avg with a ZZ4 cam.

 

Z69 thanks for the input.

Update on my tune,
Yesterday evening I took a 250 mile (round trip) road trip. the trip out was about 50 miles interstate at 70 mph, then I turn onto a 2 lane road and ran anywhere from 45 to 60 mph for around 30 miles. Next was about 15 miles of 25 to 30 and start/stop. The ride home was mostly interstate at 75/80 mph.

After 9 stops to tune I am very happy with the end result. I ended up with 22.1 mpg for the trip with lean cruise afr between 16 and 17 and normal afr between 14.2 and 15. Still have a small amound of jerking at low rpm, very light/no LV8 below 25mph but its much better than it was.

This mornings cold startup was also much better after adding some fuel to the startup area.

I'm now back at work for my 4 days of 12 hour shifts and as soon as I hit my 4 days off I'll start tuning WOT to get ready for the track

I want to thank you guys for all the help,
Dewayne