miataa

I have spent hours searching through forum posts for the answer to my problem. Why does TS read my AFR at around 2 points lower than what my MTX gauge reads.

I have followed instructions from members of this forum on where to have ground and power. No combination of different ground locations or power locations gets me a different reading...

I defaulted back to the original spots after hours of frustration. Both the ground and power have been re-soldered to the power and ground from the MTX.

When I play with numbers to calibrate, the only time it seems to get even close is when I have it set to -.64 = 7.35 // 4.6 = 22.39. It also get close at 0 = 7.35 // 3 = 22.39. and -1.2ish = 7.35 // 5 = 22.39.

When I have used the 3 different settings that come close I can't even give the car gas or it dies. The gauge will read 18,19,20 as the car dies, while TS reads the opposite direction and says 9,8,7ish before dying. TS doesn't seem to read the AFR as the mix goes richer either. TS can read 12.xx and change xx quickly, but as the 12 goes to 13 or 14, TS stays at 12. With VE analyze live on, while idling perfectly, with the settings on where TS almost matches, I can't even get the car out of the driveway, it dies.

I am fascinated by this problem. My soldering skills are definitely getting a work out. Can anyone chime in with any relevant info? I am seeing other posts say AEM widebands can have these calibration issues too, I'm about ready to throw this MTX in the trash and buy something different. I really don't want to have to do that though. Any thoughts?

ryansmoneypit

iTrader: (6)

I didn't have any problem with my mtx. MS haz a steep frustrating learning curve. Keep searching. You will find a problem.

SJP0tato

iTrader: (7)

Because you have a ground offset between the MS and your gauge. Some people report tying the sensor grounds together fixes it, others have reported it makes no difference.

What I'd do is find a good ground for the gauge, then start with the settings on page 10: http://www.innovatemotorsports.com/s...rint%201.2.pdf

Remember it's the offset, not the curve/slope that's off, so try subtracting/adding the same amount to both low and high values. Start with 0v/7.35, 5v/22.39 and see how the AFR is. Then subtract or add 0.25 on both AFR values, and see if that shifts the gauge reading closer or farther than what TunerStudio reads. Adjust as necessary.

Braineack

iTrader: (62)

have you not tried .25v = 7.35 and 5v = 22.4?

that's what I always use for innovate installs.


You still have to go through the same exercise with AEM gauges.

miataa

Yes, you gave me those numbers a few months ago. They don't work. Those numbers see 12.XX as 10.7-10.9.


I have tried grounds on my body in the engine bay, the head, a few bare metal spots in the car near the ECU location, and 2 times I have soldered it to the ECU ground close to the ECU itself. I can go through numbers again, I was using .01 increments and I spent a few hours in my car trying to get this to work. I haven't played around with advanced analog output settings in LM programmer though, would it be wise to change the update speed from the default 1/12?

Braineack

iTrader: (62)

Wouldn't hurt to double check that LM Programmer says your output is in fact 7.35-22.4 and not something odd or try the other output.

mmmjesse

dumb question. what wire from the MTX-l do you have going to the MS3x? Yellow or Brown? How do you have it wired into the MS3x? I ask this because i dont have any major problems with mine. 93 with MS3x and MTX-L.

miataa

Checked LM Programmer. LM programmer had all defaults set, except it was in lambda mode. I switched it back to AFR. With the defaults, TS is bounces quickly from 7.8-7.9 while the gauge sits at 13.xx. With 0.22 it lowers it to 7.10/7.20.
The car wouldn't start or idle with the new settings. I kept trying to start it and my gauge was showing around 20, while TS still hovered at 7.8/7.9.

I have a couple videos of TS vs the Gauge while on Lambda mode, and TS with the wideband(AFR) setting in project properties.

Changing numbers on wideband calibration for Tunerstudio and my MTX - YouTube --just changing numbers in custom WB to show the effect. 3min
Closest I have gotten MTX and TunerStudio. AFR reading. - YouTube ---closest I have come to getting the settings to match. 20sec

I bought my MS3X used. It had two yellow wires and one pink wire all going into what looked like one red wire. The person I bought the MS from said to use that red wire. When I undid the electrical tape I found that the two yellow wires weren't used, and each end was covered by tape, so the brown wire from my MTX was only connected to the pink wire, but through the long piece of red wire.

mmmjesse

I believe your problem isbyou have the brown wire connected. You should be using the yellow wore from the MTXL.

miataa

Thanks jesse. I had been using that brown wire since I was told to use that one by the guy who sold me the MS3x. That solved my problem. Finally. I have matched my MTX to my MS3x.



Next question, it seems to start and idle fine. Once I give it gas it dies. I timed it when it was hooked up to the brown wire, should I re-do the timing? I was thinking I should mess with the accel enrichment. Any tips on how to do that? Since braineack gave me the base tune is it safe to assume most settings are correct? I double checked the AFR table and the fuel VE table matched with screenshots from other forum members on here. Those tables look fine.

mmmjesse

i would probably reload the base tune and start fresh on it. what year is your car?

miataa

stock 1995.