HELP: AFR too lean
HELP: AFR too lean
Tried logging the data from O2S1 using OBDKey Bluetooth and here is what I got:
~mA~~~ EQ Ratio~~RPM
-0.121~~0.970~~~~1042
-0.027~~0.993~~~~1099
-0.238~~0.945~~~~1140
-0.215~~0.949~~~~1200
-0.051~~0.986~~~~1214
0.227~~1.097~~~~1241
0.113~~1.041~~~~1267
-0.188~~0.955~~~~1390
-0.102~~0.974~~~~1764
-0.098~~0.976~~~~2232
-0.152~~0.962~~~~2750
-0.414~~0.908~~~~3320
-0.727~~0.852~~~~3886
-0.316~~0.928~~~~4500
-0.504~~0.890~~~~5085
-0.363~~0.918~~~~5727
-0.512~~0.889~~~~6359
-0.535~~0.885~~~~6967
-0.820~~0.836~~~~7549
-0.543~~0.884~~~~8031
-0.418~~0.907~~~~8594
0.555~~~1.256~~~~8822
According to:
To convert EQ Ratio to AFR, use: AFR = {stoich}/EQ
To convert Lambda to AFR, use: AFR = Labmda/{stoich}
To convert AFR to EQ Ratio, use: EQ Ratio = {stoich}/AFR
To convert Lambda to EQ Ratio, use: EQ Ratio = 1/Lambda
To convert EQ Ratio to Lambda, use: Lambda = 1/EQ Ratio
I assume that the Stoich for RON97 petrol is 14.1 and apply "14.1/EQ Ratio". Is this equal to {14.1}/EQ Ratio? not sure what is the curly bracket means.
And my AFR looks way too lean.
~mA~~~ EQ Ratio~~RPM
-0.121~~0.970~~~~1042
-0.027~~0.993~~~~1099
-0.238~~0.945~~~~1140
-0.215~~0.949~~~~1200
-0.051~~0.986~~~~1214
0.227~~1.097~~~~1241
0.113~~1.041~~~~1267
-0.188~~0.955~~~~1390
-0.102~~0.974~~~~1764
-0.098~~0.976~~~~2232
-0.152~~0.962~~~~2750
-0.414~~0.908~~~~3320
-0.727~~0.852~~~~3886
-0.316~~0.928~~~~4500
-0.504~~0.890~~~~5085
-0.363~~0.918~~~~5727
-0.512~~0.889~~~~6359
-0.535~~0.885~~~~6967
-0.820~~0.836~~~~7549
-0.543~~0.884~~~~8031
-0.418~~0.907~~~~8594
0.555~~~1.256~~~~8822
According to:
To convert EQ Ratio to AFR, use: AFR = {stoich}/EQ
To convert Lambda to AFR, use: AFR = Labmda/{stoich}
To convert AFR to EQ Ratio, use: EQ Ratio = {stoich}/AFR
To convert Lambda to EQ Ratio, use: EQ Ratio = 1/Lambda
To convert EQ Ratio to Lambda, use: Lambda = 1/EQ Ratio
I assume that the Stoich for RON97 petrol is 14.1 and apply "14.1/EQ Ratio". Is this equal to {14.1}/EQ Ratio? not sure what is the curly bracket means.
And my AFR looks way too lean.
If I used divide the EQ Ratio by 14.7 stoich, it's even leaner...
Maybe the reading of OBDKey from stock O2S1 is Lambda instead of EQ Ratio. Then it makes sense.
The 1st graph in my previous post was calculated with {Stoich}/EQ Ratio, which is 14.1/EQ Ratio.
The 2nd graph here is assuming that the reading from OBDKey of O2S1 is Lambda and calculated with Lambda*14.7. This is assuming that the data is in Lambda, and the AFR looks correct.
Maybe the reading of OBDKey from stock O2S1 is Lambda instead of EQ Ratio. Then it makes sense.
The 1st graph in my previous post was calculated with {Stoich}/EQ Ratio, which is 14.1/EQ Ratio.
The 2nd graph here is assuming that the reading from OBDKey of O2S1 is Lambda and calculated with Lambda*14.7. This is assuming that the data is in Lambda, and the AFR looks correct.
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