Adding a Fuel Level sensor to your Holley Efi and how to set it up in software as well as dash

Wiring, and programming on how to install a fuel level sensor to your Holley Efi system and how to set up a custom gauge on your dash.
in this video i am using a 12.3 pro dash but the process is the same for the 7 inch dash and the 6.86 dash

[@CrazyCowboyBuilds]

Thanks for sharing. I’m gonna order one of these 12.3” this week

[@alshotrodgarage4779]

Fellow mustang lover here, have had 3 91-93 fox body cars...I’m liking the channel

[@charlesfields626]

You are the man! Thanks for these vids. Keep ‘em coming

[@jcnpresser]

Thanks for the info, my brother just got a 91 Camaro with a ls3 and a dominator, gonna be wiring in the fuel gauge for him, as well as setting up a 2 step off the brake pedal switch. He don’t know about the 2 step yet though, that’s gonna be a surprise! 😉

[@matttackel997]

Awesome information, Thanks for doing this one!

[@CrazyCowboyBuilds]

Do I have to add a pin to the plug that goes into the back of the Pro Dash? I got the software side figured out just need to know where to connect the 0-90ohm wire from the tank sensor!

[@jasonbrinegar6759]

Just came for a refresh before wiring this Defender 90

[@moose1992caprice]

Hey Dev. Buddy.. when you're done installing Jon Docs underglow will you make a video on how to add a fuel level guage to the Terminator Xmax ? I think it has to be in volts because thermistor isn't an option.?.? Not sure and was hoping maybe you could help.

[@MrBoostedGS]

Hi new to Holley efi and having a hard time with my 7in screen In changing or adding gauges I’m just not understanding. Do you make files for customers? I’d like to add fuel level and trans temp. Vehicle is a 98 ws6 terminator x max with factory body harness still hooked up. Thanks

[@bruizer28]

does this have to be done with ecu inputs( I am running out) or can it be wired to the pro-dash 6.86 input?

[@cturboaddict]

Any chance you have an idea of the connector that goes into the Holley Dash IO module? 558-432??? I don't really want to spend the extra money to pay for the connector when I can just go with my own wires....

[@lennyguyett9202]

In your opinion is it better to wire the fuel gauge to the ECU like you did rather than to the 12.3 pro dash? I'm asking because I can't get mine to read correctly running it through the pro dash. I also have my trans temp running to the pro dash and I'm questioning if it's reading correctly too.

[@hd100th03fatboy]

Needing to know this my self.

[@boostedthirdgenracing]

If I go from a terminator X to a dominator can I program for 3.5 Dash that came with the terminator x to see the fuel level gauge ?

[@ninerz49erz]

Can you do this with the Terminator X?

[@matthew37641]

I have like 20 inputs setup but I cant see any of them on the dash what am i doing wrong lol?

[@jameskitchens9379]

Can you control a water meth kit through the terminator X ECU?

[@morrisrodney19]

12.3 Holley do not have the tuning option unless you have a dominator of a hp . It do not show up with the terminator max

[@ford9050]

I have had a fuel gauge and for years. It has never been accurate to drive with. They say the dash screen has an Ohm buffer you are supposed to use so the fuel gauge does not bounce all around and you can accurately read the fuel level.

[@BryceSirianni]

under my type i cant choose thermistor. i only have the option of 12v, ground, digital speed, 5 volt and CAN????

[@nicholasj.markkula3658]

Same issue here, did you figure it out?

[@BryceSirianni]

@@nicholasj.markkula3658 nope. Just been guessing my fuel for 6 months now hahaha

[@frankharder9122]

So I have the fuel sender reference wire going to a configured input. Do I need to run a shared sensor ground from the ecu all the way back to the sensor ground wire? Right now I have the sensor ground wire off the sensor grounding to the frame near the tank and the ecu is not reading it

[@theholleyefiguy]

i always run a sensor ground from ecu to the sender yes

[@MK-us7bq]

Is there a fix to keep the gauge from bouncing around so much ? like after taking a turn it is all over the place ?

[@MikeSVOR]

I thought I saw 'Updates per second' in the gauge customizing list. It was default to 6 per second. Have you tried changing that to like 5 updates per minute?

[@skybirdrx5848]

Mine only shows CAN THERMISTOR ???

[@str8tdiesel07]

I quickly looked through the 6.86 pro dash and didnt see the fuel gauge option. Maybe I missed it or possibly need to update? Anybody have any experience with the 6.86?

[@williamandrade4423]

Mine is there at the bottom,the sensor isnt working just saying its full all the time

[@RecklessRegal]

What is the difference between sensor ground and chassis ground, and why do you update them to use sensor ground?

[@KCadbyRacing]

Holley has Sensor Ground Input that you wire/populate out to the Sensors (PIN A18 in J1A connector on HP and Dom.)... This assures the sensor(s) are properly grounded directly to the ECU to read accurately (rather than grounding them to the chassis)... Go to Help, Wiring Manuals & Diagrams, Pinout and you'll see that both J1A and J2A connectors (on Dominator) have Sensor Ground Input in PIN A18, plus two more in J3 and another in J4...

[@funfun8095]

Terminator X doesn't have thermistor option. What would you use?

[@theholleyefiguy]

A dominator

[@curtdog74]

Custom ohms

[@funfun8095]

@@curtdog74 Not an option. Have to do it through 7 inch dash we have, with extra harness of course.

[@curtdog74]

@@funfun8095 exactly io10 on the dash

[@funfun8095]

@@theholleyefiguy Thanks for not helping. Could have explained there is a way to make it work, if you have a Holley dash. Could try to help people more, without an attitude and telling them to spend 2000.00 for another ECU, when they can do it with a 40.00 harness, and not the 260.00 holley dash i/o harness. People suggest buying system from people like you " That will give actual support, unlike jegs, summit, etc," But haven't seen you reply to anyone without an attitude and your site never shows anything in stock. 👋

[@jacobecavalier1499]

This don’t work for term x

[@johnmatthews1152]

It will be it will be a good video if you didn't talk

[@theholleyefiguy]

so unsubscribe and piss off

[@johnmatthews1152]

@@theholleyefiguy I just come across your Channel and thought it might be something I was in sand cuz I was looking to buy a holly EFI

[@Nicholas-im8bd]

John Matthews well he doesn’t work for Holley.... he makes these free videos to help us guys using Holley out. He could give a shit less what Efi you buy