LC1 just reads 10.4 AFR

For discussing how to choose sensors and create a wiring harness for all Bowling and Grippo versions of the MegaSquirt® EFI controller.
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Army of Six
MegaSquirt Newbie
Posts: 33
Joined: Mon Jan 12, 2009 12:23 pm

LC1 just reads 10.4 AFR

Post by Army of Six »

MSII 3.0 v2.885

so i finaly figured out how to "unset" my narrowband and "set" my innovative wideband so i can view actual AFR's rather than the narrow band 0-1 V. i also selected single wide band and calibrated with AFR table. my problem is that it simply reads dead at around 10.4 AFR at idle and when i blip the throttle. i followed all the instructions when installing the LC1 and i calibrated it with no error codes.

this is a new set up that i just got to idle today. any ideas?

thanks, Vic
Matt Cramer
Super Squirter
Posts: 2951
Joined: Sat Jul 03, 2004 11:35 am

Re: LC1 just reads 10.4 AFR

Post by Matt Cramer »

Connect to the LC-1 with LogWorks and check what AFR reading you are getting there. Is that the same as in MegaTune or not? Let me know what you find and we'll take it from there.
Army of Six
MegaSquirt Newbie
Posts: 33
Joined: Mon Jan 12, 2009 12:23 pm

Re: LC1 just reads 10.4 AFR

Post by Army of Six »

Matt,

it will be difficult to install logworks (9mb file ) onto my ancient circa 1995 laptop. so what i did was simple hook up a volt meter to the wideband output of the LC1. with the engine off (basically free air) it reads 4.95 volts. once i fire it up it stays at a constant .19-.2 volts. maybe it is really running that rich? the thing that stumps me a bit is that it doesnt even flinch at the blip of the throttle.
Army of Six
MegaSquirt Newbie
Posts: 33
Joined: Mon Jan 12, 2009 12:23 pm

Re: LC1 just reads 10.4 AFR

Post by Army of Six »

one thing i noticed tonight is that with the engine off but the key on, the volt meter reads 4.95ish but the AFR display in megatune still only reads the 10.4 AFR
Matt Cramer
Super Squirter
Posts: 2951
Joined: Sat Jul 03, 2004 11:35 am

Re: LC1 just reads 10.4 AFR

Post by Matt Cramer »

MS2 code often doesn't update the AFR readings without a tach pulse.

Check the Megasquirt on a Stim, see if the AFR moves as you adjust the O2 sensor trim pot.
Army of Six
MegaSquirt Newbie
Posts: 33
Joined: Mon Jan 12, 2009 12:23 pm

Re: LC1 just reads 10.4 AFR

Post by Army of Six »

well i dont have a stim...and cant really afford one because i spent all my money on a fancy scmancy wide band O2 sensor.

i just got in from messing with it. i leaned out the map so much that it wouldnt run. and it still reads a flatline .2V

whats messed up is that if i turn the motor off and then turn the key to the run position. (car not running but O2 sensor is on) it reads a constant .2V for like 10 seconds then jumps straight to 4.99V. Its like it only has 2 voltage outputs... .2 and 4.99 V It seems like when the car is off you would see the voltage gradually go from .2V to 4.99V
Army of Six
MegaSquirt Newbie
Posts: 33
Joined: Mon Jan 12, 2009 12:23 pm

Re: LC1 just reads 10.4 AFR

Post by Army of Six »

also the narrow band output yellow wire of the LC1 was reading .4 to .5ish Volts at idle when the wide band was reading a constant .2V
Army of Six
MegaSquirt Newbie
Posts: 33
Joined: Mon Jan 12, 2009 12:23 pm

Re: LC1 just reads 10.4 AFR

Post by Army of Six »

Hey Matt...mystery solved. its a bad controller/sensor. i pulled the holley O2 wideband off of my GTO and hooked it up and it worked like a charm. fired up and idled around 15.6 afr where the LC1 was reading a flatline 10.4 afr.

so what do i need to do to get this back to you guys for a refund or exchange??

thanks, Vic
Matt Cramer
Super Squirter
Posts: 2951
Joined: Sat Jul 03, 2004 11:35 am

Re: LC1 just reads 10.4 AFR

Post by Matt Cramer »

I'll email you on this one.
Army of Six
MegaSquirt Newbie
Posts: 33
Joined: Mon Jan 12, 2009 12:23 pm

Re: LC1 just reads 10.4 AFR

Post by Army of Six »

Thank you Matt,

the guys at innovative contacted me (what great customer support i might add). they recommended that i re calibrate it which i did. it still was doing the same thing. I noticed that the .2 output voltage was the same as the voltage that it gives as the sensor is heating up. with the sensor out of the exhaust and still in free air i fired up the motor and to my surprise the V reading dropped from 4.99 to the .2V and just stayed there.

i got to thinking that maybe the control unit isnt getting a full or good 12V because i piggybacked it off of the ignition which also powers the ECU. So i hooked it up directly to the battery and it worked perfectly.

i didnt have an extra relay so i piggy backed it off of the fuel pump relay output and it seems to be working fine.

maybe this post will help someone down the road that may be experiencing the same problem.

Well, now im off to tune my baby :)

thanks again.
Vic
Matt Cramer
Super Squirter
Posts: 2951
Joined: Sat Jul 03, 2004 11:35 am

Re: LC1 just reads 10.4 AFR

Post by Matt Cramer »

Glad to hear it's working. These do need a good steady power source and a good ground.
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