Notices
MEGAsquirt A place to collectively sort out this megasquirt gizmo

AFR0 at startup and MAT calibration weirdness

Thread Tools
 
Search this Thread
 
Old Jun 25, 2014 | 12:06 PM
  #1  
asmasm's Avatar
Thread Starter
Senior Member
iTrader: (1)
 
Joined: Jul 2012
Posts: 792
Total Cats: 143
From: durham NC
Default AFR0 at startup and MAT calibration weirdness

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
Old Jun 25, 2014 | 12:41 PM
  #2  
Braineack's Avatar
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Default

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
Old Jun 25, 2014 | 12:57 PM
  #3  
asmasm's Avatar
Thread Starter
Senior Member
iTrader: (1)
 
Joined: Jul 2012
Posts: 792
Total Cats: 143
From: durham NC
Default

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.
Old Jun 26, 2014 | 08:54 AM
  #4  
Twodoor's Avatar
Senior Member
iTrader: (2)
 
Joined: Mar 2014
Posts: 628
Total Cats: 44
From: Meridian, Mississippi
Default

Originally Posted by asmasm
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.
The heater ckt for the LC1 is a large electrical load, with a battery that is marginal to begin with you are experiencing voltage drop during LC1 sensor warm up.

Keith
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
satisfied
MEGAsquirt
144
Nov 5, 2018 04:05 PM
Zaphod
MEGAsquirt
47
Oct 26, 2018 11:00 PM
nick470
MEGAsquirt
1
Sep 30, 2015 10:32 PM
vehicular
General Miata Chat
12
Sep 14, 2015 03:17 PM
PatCleary
Miata parts for sale/trade
9
Sep 11, 2015 07:53 PM




All times are GMT -4. The time now is 02:19 AM.