AFR0 at startup and MAT calibration weirdness - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


MEGAsquirt A place to collectively sort out this megasquirt gizmo

Reply
 
 
 
LinkBack Thread Tools
Old 06-25-2014, 01:06 PM   #1
Senior Member
Thread Starter
iTrader: (1)
 
Join Date: Jul 2012
Location: durham NC
Posts: 767
Total Cats: 115
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
asmasm is offline   Reply With Quote
Old 06-25-2014, 01:41 PM   #2
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,840
Total Cats: 1,786
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
Braineack is offline   Reply With Quote
Old 06-25-2014, 01:57 PM   #3
Senior Member
Thread Starter
iTrader: (1)
 
Join Date: Jul 2012
Location: durham NC
Posts: 767
Total Cats: 115
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.
asmasm is offline   Reply With Quote
Old 06-26-2014, 09:54 AM   #4
Senior Member
iTrader: (2)
 
Join Date: Mar 2014
Location: Meridian, Mississippi
Posts: 637
Total Cats: 42
Default

Quote:
Originally Posted by asmasm View Post
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
Twodoor is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
My solution for Oiltemp and Oilpressure input into Megasuirt (MS3) Zaphod MEGAsquirt 41 01-24-2016 01:25 PM
MS PNP requires reading and following directions??? satisfied MEGAsquirt 141 10-06-2015 11:44 AM
Bizarre connection issue? nick470 MEGAsquirt 1 09-30-2015 11:32 PM
Mystery Engine Trouble. Halp, mt.net! vehicular General Miata Chat 12 09-14-2015 04:17 PM
1995 Miata parts, coilover springs, PatCleary Miata parts for sale/trade 9 09-11-2015 08:53 PM


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 02:30 PM.