MTX-L gauge vs TS AFR
06-20-2014, 07:13 PM
#1
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MTX-L gauge vs TS AFR
Fresh install of a rev built MS3 basic last night, it has a db37 wiring harness that has
BLACK/GREEN - Analogue sensor ground
BLACK/YELLOW - Ground / Heater Ground (LC-1 Wideband)
Well, when I hook the MTX-L gauge's ground up to the black/green it doesn't power up. when I hook the MTX-L gauge's ground to the BLACK/YELLOW it powers up, but then MS reads about .6ish AFR leaner than my gauge does.
I tried twisting the grounds together (black/yellow and black/green) and hooking the mtx-l ground to those twisted together is the same as hooking it to black/yellow.
Rev asked what WB i had and i assume he punched the numbers in, but just to be safe I got the voltages from the manual and punched them in to the calibrate AFR Table under Tools... exactly the same.
So, it seems like a grounding issue to me, but where the hell should I ground it if the ground built into the MS is giving me faulty readings? I suppose i *COULD* just calibrate around the problem... but that sounds like bandAIDS to me.
BLACK/GREEN - Analogue sensor ground
BLACK/YELLOW - Ground / Heater Ground (LC-1 Wideband)
Well, when I hook the MTX-L gauge's ground up to the black/green it doesn't power up. when I hook the MTX-L gauge's ground to the BLACK/YELLOW it powers up, but then MS reads about .6ish AFR leaner than my gauge does.
I tried twisting the grounds together (black/yellow and black/green) and hooking the mtx-l ground to those twisted together is the same as hooking it to black/yellow.
Rev asked what WB i had and i assume he punched the numbers in, but just to be safe I got the voltages from the manual and punched them in to the calibrate AFR Table under Tools... exactly the same.
So, it seems like a grounding issue to me, but where the hell should I ground it if the ground built into the MS is giving me faulty readings? I suppose i *COULD* just calibrate around the problem... but that sounds like bandAIDS to me.
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06-20-2014, 07:22 PM
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As an aside, i did not have this issue with the MS2E
EDITing so I don't spam: just found this post with both rev and brain weighing in, and it sounds like just adjusting the calibration is the way to go.
http://forum.miata.net/vb/showthread.php?t=435219
EDITing so I don't spam: just found this post with both rev and brain weighing in, and it sounds like just adjusting the calibration is the way to go.
http://forum.miata.net/vb/showthread.php?t=435219
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06-20-2014, 08:32 PM
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The simple fix is to figure out how far off it is and adjust your numbers in the cal table to make it match the gauge reading. I am using 6.4 for the low and 21.4 for the high. The other option is to have Reverent build you an input box and have the digital output from the gauge go to the box and then from the box to the MS3... then it will read exactly the same.
Keith
Keith
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06-21-2014, 12:53 AM
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That's a bad fix because the offset changes with how much the heater needs to run to maintain temperature.
The correct fix is to ground the MTX-L at the other end of the MS3, at a power ground wire, close to the MS3 chassis. The error shrinks to about 0.1~0.2 AFR.
I helped my friend Ian troubleshoot this. I've emailed Reverant already. There are 2 causes of this:
1) Innovate combined the power and signal grounds into a single wire (stupid).
2) There is too much resistance from the DB37 power ground connection, to the point in the MS3 PCB where the signal ground and power ground meet. There is less resistance from the point I recommend connecting it. But there is still some, thus the 0.2 AFR error.
The correct fix is to ground the MTX-L at the other end of the MS3, at a power ground wire, close to the MS3 chassis. The error shrinks to about 0.1~0.2 AFR.
I helped my friend Ian troubleshoot this. I've emailed Reverant already. There are 2 causes of this:
1) Innovate combined the power and signal grounds into a single wire (stupid).
2) There is too much resistance from the DB37 power ground connection, to the point in the MS3 PCB where the signal ground and power ground meet. There is less resistance from the point I recommend connecting it. But there is still some, thus the 0.2 AFR error.
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06-21-2014, 01:32 PM
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That's a bad fix because the offset changes with how much the heater needs to run to maintain temperature.
The correct fix is to ground the MTX-L at the other end of the MS3, at a power ground wire, close to the MS3 chassis. The error shrinks to about 0.1~0.2 AFR.
I helped my friend Ian troubleshoot this. I've emailed Reverant already. There are 2 causes of this:
1) Innovate combined the power and signal grounds into a single wire (stupid).
2) There is too much resistance from the DB37 power ground connection, to the point in the MS3 PCB where the signal ground and power ground meet. There is less resistance from the point I recommend connecting it. But there is still some, thus the 0.2 AFR error.
The correct fix is to ground the MTX-L at the other end of the MS3, at a power ground wire, close to the MS3 chassis. The error shrinks to about 0.1~0.2 AFR.
I helped my friend Ian troubleshoot this. I've emailed Reverant already. There are 2 causes of this:
1) Innovate combined the power and signal grounds into a single wire (stupid).
2) There is too much resistance from the DB37 power ground connection, to the point in the MS3 PCB where the signal ground and power ground meet. There is less resistance from the point I recommend connecting it. But there is still some, thus the 0.2 AFR error.
With issue #2, is the delta a constant 0.2 (AFR)? Or does it drift significantly?
My plan when I have the time is to utilize a Tiny I/O board to feed the digital signal to the MS3X over CANBUS. See TinyIOx v1.0 Board
Please us know what Reverant has to say.
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06-23-2014, 09:31 AM
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I have been struggle with this exact same issue for a while now (MTX-L and Reverant built MS3X). I also observe that the delta between the MTXL display and readings in TS from the MS3X varies. I have gotten it dialed in at times using the MTX-L settings or in TS by setting up a custom WBO calibration, only to find that the delta has drifted.
With issue #2, is the delta a constant 0.2 (AFR)? Or does it drift significantly?
My plan when I have the time is to utilize a Tiny I/O board to feed the digital signal to the MS3X over CANBUS. See TinyIOx v1.0 Board
Please us know what Reverant has to say.
With issue #2, is the delta a constant 0.2 (AFR)? Or does it drift significantly?
My plan when I have the time is to utilize a Tiny I/O board to feed the digital signal to the MS3X over CANBUS. See TinyIOx v1.0 Board
Please us know what Reverant has to say.
I also have it so that TunerStudio sees values slightly LEANER than the gauge does, that way when I VEAL I'll be adding 0.2afr worth of fuel, and not pulling it, so I'm erring on the side of being slightly rich instead of slightly lean.
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06-23-2014, 10:01 PM
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My plan when I have the time is to utilize a Tiny I/O board to feed the digital signal to the MS3X over CANBUS. See TinyIOx v1.0 Board
Please us know what Reverant has to say.
Please us know what Reverant has to say.
Since I havn't done serious soldering since ETMS (advanced trouble shooting and repair school) in the NAVY 15 years ago I let him put my stuff together 
Keith
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06-24-2014, 12:05 AM
#10
That's a bad fix because the offset changes with how much the heater needs to run to maintain temperature.
The correct fix is to ground the MTX-L at the other end of the MS3, at a power ground wire, close to the MS3 chassis. The error shrinks to about 0.1~0.2 AFR.
I helped my friend Ian troubleshoot this. I've emailed Reverant already. There are 2 causes of this:
1) Innovate combined the power and signal grounds into a single wire (stupid).
2) There is too much resistance from the DB37 power ground connection, to the point in the MS3 PCB where the signal ground and power ground meet. There is less resistance from the point I recommend connecting it. But there is still some, thus the 0.2 AFR error.
The correct fix is to ground the MTX-L at the other end of the MS3, at a power ground wire, close to the MS3 chassis. The error shrinks to about 0.1~0.2 AFR.
I helped my friend Ian troubleshoot this. I've emailed Reverant already. There are 2 causes of this:
1) Innovate combined the power and signal grounds into a single wire (stupid).
2) There is too much resistance from the DB37 power ground connection, to the point in the MS3 PCB where the signal ground and power ground meet. There is less resistance from the point I recommend connecting it. But there is still some, thus the 0.2 AFR error.
Where exactly are you running the ground for the mtxl to reduce the error? I know of a few grounds under the hood on my NA
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06-24-2014, 10:45 PM
#14
So 2a or 2b? Here is a wiring diagram.
https://www.miataturbo.net/attachmen...chmentid=90579
And id be fine tapping into the stock wire on the stock connector that plugs into the ms3 correct?
https://www.miataturbo.net/attachmen...chmentid=90579
And id be fine tapping into the stock wire on the stock connector that plugs into the ms3 correct?
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06-28-2014, 02:49 PM
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Sounds like moving the ground is even more important on LC-2 as both the gauge and the MS3-Basic are using Analog signals. And, if I understand correctly, if I go to the digital conversion into the MS, then that is the reading I should trust, and correct the G5 gauge to match it. Still move the ground so the correction to the gauge is consistent.
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