AFR0 at startup and MAT calibration weirdness
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I just got my Reverent MS3 installed last night along with his CAN interface and an LC2. I am getting an AFR0 error on startup that lasts 5-10 seconds and then goes away. The car runs like **** during that window and then as soon as the CEL clears its runs really well. My LC2 is not giving me any blink codes.
Thoughts on how to nail down the cause? My battery seems marginal, a multimeter on the posts gives me 12.4v but I get no 9 blink code out of the LC2 for low voltage.
Also,
Which tables are people using to calibrate IAT? The two charts I have found give me a 10 degree delta :
-4 / -20 16150
104 / 40 1150
176 / 80 330
If I use this chart I get a number that matches my CLT within a degree:
Temperature Ohms
48 degrees F 7000
87 degrees F 1930
146 degrees F 560
Thoughts on how to nail down the cause? My battery seems marginal, a multimeter on the posts gives me 12.4v but I get no 9 blink code out of the LC2 for low voltage.
Also,
Which tables are people using to calibrate IAT? The two charts I have found give me a 10 degree delta :
-4 / -20 16150
104 / 40 1150
176 / 80 330
If I use this chart I get a number that matches my CLT within a degree:
Temperature Ohms
48 degrees F 7000
87 degrees F 1930
146 degrees F 560
#2
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are you disabling EGO during startup? it should be disabled for at least the amount of time it takes for the LC2 to warmup; the LC1 on my car was about 25 seconds.
if so, then you need to tune.
are you metering at the battery or injectors/ecu?
I use GM AIT, and RX7 (S4 & S5) for CLT
if so, then you need to tune.
are you metering at the battery or injectors/ecu?
I use GM AIT, and RX7 (S4 & S5) for CLT
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I was measuring at the battery posts. My ego parameters are set to 40 seconds after start and above 113 F CLT.
When my wife gets home I will try starting the car with jumpers on the battery to rule out a temporary voltage dip.
During the 40 seconds EGO is off should I expect the AFR0 error? Googling AFR0 at startup didn't get me anything so I was assuming it is not normal.
Either way it sounds like I just need to adjust the ASE and maybe warmup enrichment.
When my wife gets home I will try starting the car with jumpers on the battery to rule out a temporary voltage dip.
During the 40 seconds EGO is off should I expect the AFR0 error? Googling AFR0 at startup didn't get me anything so I was assuming it is not normal.
Either way it sounds like I just need to adjust the ASE and maybe warmup enrichment.
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I was measuring at the battery posts. My ego parameters are set to 40 seconds after start and above 113 F CLT.
When my wife gets home I will try starting the car with jumpers on the battery to rule out a temporary voltage dip.
During the 40 seconds EGO is off should I expect the AFR0 error? Googling AFR0 at startup didn't get me anything so I was assuming it is not normal.
Either way it sounds like I just need to adjust the ASE and maybe warmup enrichment.
When my wife gets home I will try starting the car with jumpers on the battery to rule out a temporary voltage dip.
During the 40 seconds EGO is off should I expect the AFR0 error? Googling AFR0 at startup didn't get me anything so I was assuming it is not normal.
Either way it sounds like I just need to adjust the ASE and maybe warmup enrichment.
Keith
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