What options for logging fuel psi on LS1 C5 vette

[abc]

I am currently using an AEM WBO2 serial to USB to log my WB AFR but would also like to log fuel psi. I know I need to plumb in a fuel psi sensor, but from there what are the options for logging it and how to's?

Could I use another serial to usb cable and plug it into another usb port on the lap top? How many options can you guys help me with and in your opinions what is the best route?
I currently use the MPVI 2. Could I upgrade that to the pro suite and then how do I log fuel psi?

If the info. is already here, please point me to it, my google fue may not be working well.

[TheMechanic]

Upgrade to a pro feature set and use the analog input.
https://www.hptuners.com/product/pro...set-for-mpvi2/

https://www.hptuners.com/help/VCM-Sc...g_channels.htm

https://www.hptuners.com/help/VCM-Sc...pro_inputs.htm

[blindsquirrel]

You can add a pin to the PCM connector and log it as EGR Position, assuming your OS has the EGR enable/disable options. But no tune file posted, so...

[abc]

tres in car 080623.hpt

Current tune

[blindsquirrel]

screenshot.23-01-2024 19.48.06.png screenshot.23-01-2024 19.48.20.png

Diagram is from a P01 truck with EGR, you'd need to add a wire as the Vette didn't come with it.

[abc]

I'm not sure if you took that pic from my tune file or not but I don't see the enable tab when I look at it on my end?hp egr.png

[blindsquirrel]

tres in car 080623 EGR enabled.hpt

[abc]

Even when I open the file you attached, the enable button is not there. Why do you think I can't see it on my end?
egr enable.png

[abc]

Upgrade to a pro feature set and use the analog input.
https://www.hptuners.com/product/pro...set-for-mpvi2/

https://www.hptuners.com/help/VCM-Sc...g_channels.htm

https://www.hptuners.com/help/VCM-Sc...pro_inputs.htm

If I understand this option correctly, the EIO is basically a hub to connect up to 4 external sensors that then could be logged continuously when the MPVI2 pro is attached to the OBD2 port along with the EIO is attached to the MPVI2 pro, do I have it correct?
If I am correct, I like the idea of being able to log without having the laptop open, USB cables connected, and running on the front seat.

Am I also correct in assuming I could use a 12volt to 5volt dc converter to power the fuel psi transducer, then run the sensor wire and ground to a DB9 to USB adapter and plug directly into the lap top?
I'm not saying I want to do it this way, I just want to verify it could be done this way if needed.

Do I also assume the fuel psi transducer does not need any type of controller before it gets to the EIO like the WBO2 sensor does?

[blindsquirrel]

Some things have been removed from newer versions of the editor. I keep an old version kicking around for situations like this.

If your pressure sensor is a 0-5v output, nothing else is needed. You can use one of the existing 5Vref circuits already feeding the other sensors, you do not need a separate source. These things are very low current, you will not be overloading anything by adding one more sensor to the ones already on the car.

[abc]

How can I get a copy of the old suite version, are they readily available here somewhere? Is it something you would be willing to send via e-mail or attach as a file here?

If I wanted to just use an existing 5v supply, would I just properly splice into the source for another sensor, such as the AC psi and be able to run both at the same time?

[blindsquirrel]

All of the 5-volt sensors are fed by a single source from inside the PCM. There's one supply that goes to multiple pins. Adding one more tapped into an existing 5v wire (any of them, they are all the same) is fine.

Later ECMs have multiple internal feeds, each one running multiple sensors. But the Gen3's only have one that feeds all the 5v pins.

[blindsquirrel]

screenshot.24-01-2024 21.05.50.png

[abc]

Thank you for taking the time to work through this with me, I appreciate you.

To clarify I understand the work flow: Splice into the grey wire for eng. oil psi 5v supply (pin 7 of the PCM, circuit 596) and attach that to the 5v supply for the fuel psi transducer. Run the sensor signal wire and reference ground back in the cab where they will be connected to a usb to DB9 (RS232) adapter. Set up a channel in HPT to read an external 0 to 5v sensor, call it Fuel Psi. Look correct?

If you were going to do it, would you consider this an acceptable option?

What would your preferred method be?

Would you also prefer using the MPVI pro setup to be able to log without using the laptop connected?

[blindsquirrel]

Not sure about being able to log it through Serial. I would just run the transducer signal to the EGR Position pin in the PCM, and log EGR Position in the scanner as a raw voltage, and then apply the math to turn Volts into PSI.

Logging without the laptop connected is a shiny object, I don't think that's very useful for anything real.

[abc]

Not sure about being able to log it through Serial.

Anybody else tried this?

[gametech]

The scanner expects specific serial data from the serial ports, which is why the options in the software are configured for several different common brand names of widebands and such. I do not believe the software would have any way to make sense of some random 0v-5v signal plugged into your serial port with or without a usb adapter. Something like your egr port input is by far the simplest way, although if you had the mpvi pro you could use one of the analog inputs to it. And just in case I overlooked the answer in a previous post, the fuel pressure transducer does NOT require any type of controller. Also, in case it was not specified, the file modification they gave you in a previous post with the egr enabled will enable your egr whether your software shows the enable flag or not. The way you will be able to tell if it is enabled or not is to log egr as a channel in your scanner. If it shows exactly 0 volts, it is disabled. If it shows some tiny fluctuating little millivolts, it is enabled with nothing hooked to it.
edit-- Just to be on the safe side, I checked that file to make sure the egr spark advance table was zeroed out. You should be good.

[abc]

The scanner expects specific serial data from the serial ports, which is why the options in the software are configured for several different common brand names of widebands and such. I do not believe the software would have any way to make sense of some random 0v-5v signal plugged into your serial port with or without a usb adapter.

Do you think the software team at HPT could and/or would be able to answer this question? If so where should I post this question for them to see it?

Where can I get a copy of the software that will let me enable and disable the EGR function?

[blindsquirrel]

Archived versions of the software are not available unless you find some non-HPT source willing to distribute them. Settings were removed because of lawyers. Versions after 4.8.7 started having things taken out.

The file you posted originally has the EGR disabled. The one I modified and reposted has EGR enabled (and no other changes, since you didn't originally have EGR none of the other related tables are populated from stock). You can copy any future changes into either file to enable/disable the EGR.

[gametech]

I am still a bit curious as to exactly what pins of the db9 connector were going to be chosen to input an analog voltage signal.