Megasquirt wideband problem

Boosted306!

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Apr 23, 2020
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I have a foxbody with a stock 302 shortblock, n41 cam, gt40p heads, seimens 60lb injectors, ported gt40p intake and a on 3 turbo kit. I finally have everything put together and im trying to get the car ready to drive. I have the innovate mtxl hooked up in the on3 downpipe. I have it wired to pin 21 and the jumper is set right. The problem im having is the wideband is always lean. At idle its reading 22.4 and when i try to autotune it, it says 02 out of range. I have only the wideband hooked up right now and no 02 sensors. Im new to the megqsquirt game so please bear with me.
 
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a91what

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Mod Dude
Apr 6, 2011
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Did you calibrate the O2 sensor in the software under the tools menu?
if you have then you will have to manually adjust the fuel in the VE table until the O2 reads in range, this is assuming you have the WB wired in correctly
 

Boosted306!

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Apr 23, 2020
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Your talking about calibrating it and writng it to control then yes i did that. Its either really lean 22.4 or really rich 9.2. What does 02 sensor out of range when i try to autotune it mean? Does that mean its just not the right a/f ratio thats in the afr table? I wired the yellow wire from the mtxl to the 02 pin in the back of the megasquirt mspnp2. Im sure the cam overlap isnt helping anything but like i said its either really leab or really rich. I mess with the table and its stuck on those 2 numbers
 

Blown88GT

Founding Member
Nov 13, 1999
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Palm Beach Gardens, FL
I have a foxbody with a stock 302 shortblock, n41 cam, gt40p heads, seimens 60lb injectors, ported gt40p intake and a on 3 turbo kit. I finally have everything put together and im trying to get the car ready to drive. I have the innovate mtxl hooked up in the on3 downpipe. I have it wired to pin 21 and the jumper is set right. The problem im having is the wideband is always lean. At idle its reading 22.4 and when i try to autotune it, it says 02 out of range. I have only the wideband hooked up right now and no 02 sensors. Im new to the megqsquirt game so please bear with me.
Pin 21 indicates you have the DIYAutotune MSPNP2, correct?
Pin 21 is on the Options Port.
The instructions on their website are incomplete. You have to remove the J6 jumper if you use pin-21 on the Options Port.
Those DIY guys never listen to anyone. I've told them many times to fix their instructions.

If I had the same model, I would have used an ohmmeter to confirm this but I can guarantee that the center pin on J6 is connected to pin-21 on the Options Port.
The MS is trying to look at the WBO2 output & the left or right NBO2 output simultaneously. That's never going to work!

Several jumpers are located on the lower, black circuit board inside the MSPNP. These are accessible by removing the top cover and are indicated as depicted below. However, these dictate the platform with which the MSPNP is design for. The only jumper that should be changed, if desired, is J6.
jumpers.jpg

Place a jumper between "O2 Sensor" and "J8-29" to connect the right bank OE O2 sensor the MSPNP. Likewise, connect the jumper between "O2 Sensor" and "J8-43" to connect the left bank OE O2 sensor.
 
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Boosted306!

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Apr 23, 2020
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You're right i put the jumper on j8-43 and im only using the wideband for right now. I will install the 02 sensor harness tomorrow and run a 02 in one of the headers. I had to remove the downpipe to re-tighten the copper header gasket cause there was a slight leak. I will install the 02 harness and the correct narrowband sensor and take a data log. Im seriously contemplating buying one of the pmas hpx-e mass air flow sensors and loading rhe teansfer table and using that lol. Thanks for the help
 

a91what

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Apr 6, 2011
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Why are you bothering running a narrowband sensor? There is only one O2 sensor input on the ms2pnp, you cannot run a WB and a narrowband at the same time with ECU feedback.
Switching to maf will not fix this basic issue. Please provide me with how you wired it and what instructions you used.
A datalog so I can check the voltage at the input pin.
 

Boosted306!

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Apr 23, 2020
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Im only using my innovate mtxl right now. I planned on using only the wideband and no narrowband. The yellow wire that comes off of mtxl is wired to the option port pin 21 on the mspnp2. The jumper in the pnp2 is set to the j8-43 port because on latemodel they show you how to hook it up and thats what i did. Im not using a narrowband sensor and i really dont plan on it. The gauge is reading the same as the megasquirt its either real lean or real rich. When i try to use autotune it says 02 out of range. Im guessing it says that cause i didnt put the jumper in the right spot because i didnt use a a narrowband sensor. Tomorrow ill get the data log thanks for the help
 

Boosted306!

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Apr 23, 2020
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Question regarding this jumper on the j6 port now. If i wanna just use the wideband what do i do with the j6 port. Do i leave it blank, no jumoer at all and leave the wideband hooked up to pin 21 in the options port?
 

atey950

Founding Member
Aug 5, 1999
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I just installed the same setup and I used the jumper according to the instruction. No problems. You have to calibrate the wideband sensor by turning on the ignition with the sensor removed and unplugged for 30 seconds - the display will read ‘e2’. Next, connect the plugs and then turn the ignition on. First it will read ‘htr’, then after about 15 seconds it will show the ambient air fuel. After all that is done, screw in the sensor.