no o2 sensor signal

For discussing Phil Tobin's TunerStudio MS is the MegaSquirt edition of TunerStudio, a next generation tuning application. It provides the ability to configure and tune all MegaSquirt controllers and is 100% compatible with MegaTune ini files and msq's.

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zabster57
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Joined: Tue Apr 16, 2013 6:59 pm

no o2 sensor signal

Post by zabster57 »

Hi, I've just converted from MS1 to MS2. I've installed an innovate mtx wideband sensor too. My problem is that I get no signal to the oxygen sensor gauge in tunes studio. The gauge goes red and says something like 7.4 volts. The meter in the car appears to work OK. If i disconnect the wideband and connect the narrow band that worked before I get zero. The wire in the harness is good, I checked it with an ohm meter. I've changed the settings to innovate default wide band as per instruction and nothing. I've set all settings to narrow band and still nothing. Any thoughts?
kjones6039
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Re: no o2 sensor signal

Post by kjones6039 »

Have you re-calibrated your AFR for the MTX in TunerStudio?

Ken
1979 Corvette - 383 CID SBC w/ Holley Pro-Jection 900 CFM TBI, 4-85 lb lo-z injectors & Walbro 255 pump
MS2 v3 w/ms2extra 3.4.0 Release
36-1, Delphi LS2/7 coils in wasted spark, driven by v2.0 logic board from JBPerformance
Spartan Lambda Sensor from 14point7
zabster57
MegaSquirt Newbie
Posts: 7
Joined: Tue Apr 16, 2013 6:59 pm

Re: no o2 sensor signal

Post by zabster57 »

Ken
Where is that? I followed the directions on the DIYAutoTune.com web site FAQ's. Is that the same as you are suggesting?
Strange thing is that the narrow band doesn't work either if I hook it up instead of the wideband and change all the settings to NB in tuner studio. Is there somewhere else I should look? Not makings sense to me.

Ray
LT401Vette
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Re: no o2 sensor signal

Post by LT401Vette »

On the main menu under "Tools"

Tools --> Calibrate AFR...
Phil Tobin
EFI Analytics, helping to simplify EFI with Next Generation tuning software.
http://www.tunerstudio.com/
http://www.efiAnalytics.com/MegaLogViewer/
Android Shadow Dash MS: http://tunerstudio.com/index.php/shadowdashmsmenu
zabster57
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Posts: 7
Joined: Tue Apr 16, 2013 6:59 pm

Re: no o2 sensor signal

Post by zabster57 »

Yes, I did that. But I see something that I want to try.
Either way, any idea why it won't recognize my NB sensor when I try to switch back and try to use it? Something is telling megasquiirt it is lean (7.4 V on wideband) or zero on narrow band but the dash mounted AFR gauge is showing "good" numbers. I'm missing something simple since the engine is running , so I believe the AFR gauge.
Any other thoughts if trying the "Calibrate AFR table" again doesn't work.
Thanks.
DonTZ125
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Re: no o2 sensor signal

Post by DonTZ125 »

The way the WB and NB sensors are handled by TS are very different, so it seems reasonable that you have to re-configure the project when you change sensors. Go to Project / Properties / Settings, and select 'Narrowband Sensor (Default)'. Once that's done, now go to Tools / Calibrate AFR Table.
LT401Vette
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Re: no o2 sensor signal

Post by LT401Vette »

What version firmware are you using?

the 3.83 firmware needs to use the beta TunerStudio.
http://www.efianalytics.com/TunerStudio/beta/

The Calibration tables don't write with 2.0.x as 3.83 uses the new protocol and the calibration tables need to be written in 256 byte blocks. 2.0.x doesn't know to do that.

7.4V is very high, it shouldn't be over 5v.
Phil Tobin
EFI Analytics, helping to simplify EFI with Next Generation tuning software.
http://www.tunerstudio.com/
http://www.efiAnalytics.com/MegaLogViewer/
Android Shadow Dash MS: http://tunerstudio.com/index.php/shadowdashmsmenu
zabster57
MegaSquirt Newbie
Posts: 7
Joined: Tue Apr 16, 2013 6:59 pm

Re: no o2 sensor signal

Post by zabster57 »

I am using firmware 2.920. I was running MSI for a while successfully. Just swapped out the 4 pin GM module for a 7 pin, got a newer computer to be able to run tuner studio, bought tuner studio, loaded the firmware for MSII and everything works but the O2. I agree 7.4 is way out which is the nature of my question. This is telling me something is wrong or leaner than lean! I switched the wires back to NB sensor (changing back to NB in TS)and get essentially zero, again something wrong or leaner than lean. I have switched from WB to NB a couple of times in Tuner Studio when changing sensors. I will double check this again just to make sure. I even went and tied the ground and power to the WB gauge to the same as the MSII. I'm just wondering if it my stupidity using TS or could there a hardware issue I don't know about. Keep throwing ideas at me, thanks
Ray
LT401Vette
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Re: no o2 sensor signal

Post by LT401Vette »

Yep... I think 2.92 got the new protocol too.

Try the beta TunerStudio, then calibrate the AFR with that.
Phil Tobin
EFI Analytics, helping to simplify EFI with Next Generation tuning software.
http://www.tunerstudio.com/
http://www.efiAnalytics.com/MegaLogViewer/
Android Shadow Dash MS: http://tunerstudio.com/index.php/shadowdashmsmenu
kjones6039
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Re: no o2 sensor signal

Post by kjones6039 »

Just one quick point.............
This is telling me something is wrong or leaner than lean!
7.4 AFR is not lean! It is way rich.

Ken
1979 Corvette - 383 CID SBC w/ Holley Pro-Jection 900 CFM TBI, 4-85 lb lo-z injectors & Walbro 255 pump
MS2 v3 w/ms2extra 3.4.0 Release
36-1, Delphi LS2/7 coils in wasted spark, driven by v2.0 logic board from JBPerformance
Spartan Lambda Sensor from 14point7
DonTZ125
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Re: no o2 sensor signal

Post by DonTZ125 »

He's not reading 7.4 AFR - he's reading 7.4 volts! Considering this is supposed to be a 0-5v system, this is very odd ...
zabster57
MegaSquirt Newbie
Posts: 7
Joined: Tue Apr 16, 2013 6:59 pm

Re: no o2 sensor signal

Post by zabster57 »

Don is correct, Not 7.4 AFR, 7.4 volts which IS odd on a 0-5 volt supposed signal. Now you are starting to understand my problem. It doesn't make sense and I am wondering where to look. The gauge in the car responds favorably to changes in the VE table. That is if I lean or fatten up the mixture according to the gauge the engine responds accordingly. I want to start autotune and, well without an O2 signal... Could I need to check something in the MS itself?

I am going to be away from my vehicle for a few days but please toss ideas my way, I'll get to the car in about a week and try them all. Thanks all for any ideas and help

Ray
kjones6039
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Re: no o2 sensor signal

Post by kjones6039 »

Yep...........

7.4 volts would certainly be very lean!

Ken
1979 Corvette - 383 CID SBC w/ Holley Pro-Jection 900 CFM TBI, 4-85 lb lo-z injectors & Walbro 255 pump
MS2 v3 w/ms2extra 3.4.0 Release
36-1, Delphi LS2/7 coils in wasted spark, driven by v2.0 logic board from JBPerformance
Spartan Lambda Sensor from 14point7
kjones6039
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Posts: 618
Joined: Sat Jul 22, 2006 7:02 pm
Location: Eureka, Nevada USA
Contact:

Re: no o2 sensor signal

Post by kjones6039 »

I am curious......

Exactly where are you measuring 7.4 volts?

Ken
1979 Corvette - 383 CID SBC w/ Holley Pro-Jection 900 CFM TBI, 4-85 lb lo-z injectors & Walbro 255 pump
MS2 v3 w/ms2extra 3.4.0 Release
36-1, Delphi LS2/7 coils in wasted spark, driven by v2.0 logic board from JBPerformance
Spartan Lambda Sensor from 14point7
zabster57
MegaSquirt Newbie
Posts: 7
Joined: Tue Apr 16, 2013 6:59 pm

Re: no o2 sensor signal

Post by zabster57 »

Ken

It is what the gauge on the tuner studio is showing me, along with a red gauge. I haven't had a chance to actually put a voltmeter on it, I plan on doing this when I get back. I know it does not make sense which is why I was hoping somebody knew what i did wrong to get a reading on the dashboard like this.

ray
kjones6039
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Re: no o2 sensor signal

Post by kjones6039 »

zabster57 wrote:Ken

It is what the gauge on the tuner studio is showing me, along with a red gauge. I haven't had a chance to actually put a voltmeter on it, I plan on doing this when I get back. I know it does not make sense which is why I was hoping somebody knew what i did wrong to get a reading on the dashboard like this.

ray
Got it!

Yes, I would certainly be checking that voltage with a good DVM...........

Ken
1979 Corvette - 383 CID SBC w/ Holley Pro-Jection 900 CFM TBI, 4-85 lb lo-z injectors & Walbro 255 pump
MS2 v3 w/ms2extra 3.4.0 Release
36-1, Delphi LS2/7 coils in wasted spark, driven by v2.0 logic board from JBPerformance
Spartan Lambda Sensor from 14point7
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