Autometer wideband with megasquirt pnp

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You can just ground the negative and run the positive source to the ecu. Should be able to scale in tunerstudios or it might have a drop down selection for the auto meter gauge.
 
Looking back at it you might just need to attach the positive to the megasquirt input. On an aem there is a second wire you ground to enable the output. I’d just ground them both, but as long as the positive gives 0-5 volts then that’s all that matters. The ecu will interpret that
 
I have the autometer pn4379 and it is not programmable. The wideband has a negative and positive output for the ecu. Do I use both? It is a 0-4v gauge. Do I need to scale for this wideband or what? Thanks for the help
The stock Ford computer will not run off of a wideband O2 sensor. It needs the original Ford O2 sensors to work properly.
 
You cant just ground both of them, take the heater ground to chassis and the sensor ground needs to go to the ecu.

Here is why, all the sensors are monitored as a differential voltage if you simply ground the sensor anywhere then it may have a voltage drop between the two controllers over the chassis ground. Taking the sensor ground to the ecu ensures that the voltage offset differential between the two devices is at a minimum. Any installation other than this method is technically not correct.

If you tell me what MS system you are using exactly I can tell you where to connect them.
 
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You cant just ground both of them, take the heater ground to chassis and the sensor ground needs to go to the ecu.

Here is why, all the sensors are monitored as a differential voltage if you simply ground the sensor anywhere then it may have a voltage drop between the two controllers over the chassis ground. Taking the sensor ground to the ecu ensures that the voltage offset differential between the two devices is at a minimum. Any installation other than this method is technically not correct.

If you tell me what MS system you are using exactly I can tell you where to connect them.
On the mspnp, is it not setup somewhat similar to a pimp system? The ms controller only needs to see the 0-5v from the analog output to a signal input. Shouldn’t it not matter if it’s grounded to the ecu? I’ve ran it this way on several cars and never had any inconsistencies.
 
On the mspnp, is it not setup somewhat similar to a pimp system? The ms controller only needs to see the 0-5v from the analog output to a signal input. Shouldn’t it not matter if it’s grounded to the ecu? I’ve ran it this way on several cars and never had any inconsistencies.
any inconsistencies that you have noticed perhaps.

All ECU have two ground planes internally, one for the digital inputs [noisy stuff] this one is basically chassis ground inside the case. The second is the analog ground [all the 0-5v sensors ect.] this one is tied to the main ground plane at a single junction point inside the ECU case to isolate it from noise.
Grounding analog sensors anywhere but to the actual sensor rtn or sensor ground wiring to the ecu means that you will have a voltage offset over the chassis ground. Even grounding those sensors at the chassis ground right at the ecu can induce noise and voltage offset.

pages 13 and 14 sum up this idea with pictures, however this is not just a megasquirt thing... this is an ANY electronics thing. If the wideband controller you are using does not have a seperate sensor ground from the heater ground you should buy a better controller, it is not designed correctly. This is a moot point if the device you are using is capable of serial or canbus communication.

 
All Numbers I see on the megasquirt match up exactly to the readout on the wideband controller. Good enough for me.
Depends on the WB controller, if you are using something like the spartan2 it comes with a spreadsheet that is used to account for this voltage offset from an improper installation. Even something like powering the WB from a different source than the ECU relay for instance can cause this discrepancy.
 
Depends on the WB controller, if you are using something like the spartan2 it comes with a spreadsheet that is used to account for this voltage offset from an improper installation. Even something like powering the WB from a different source than the ECU relay for instance can cause this discrepancy.
I can see that. The aem I’m using was originally tied to my old quarterhorse using the 5v signal input from the egr valve. It worked well then, with the analog output and wb controller both grounded to 2 different places - independent of the eec.

I figured “Why not try it with the ms?” And It worked just using the preloaded settings in the tunerstudios drop down menu. While it’s not ideal in theory, it works in practice. Kind like how I’ve used mechanical relays for pwm nitrous control lol.

Speaking of which, I was thinking today I still need to try out those damn nitrous settings you sent me awhile back.