How to Move Flex Sensor Ground wire in sloppy PNP harnesses

very very few people have an issue here where their flex fuel % is erratic no matter what they do, on my older harnesses the ground wire was on the chassis ground, if you move it to the sensor ground this will fix it.
quick showing you how to do it.

[@HTMR]

Yup. I was one of them. Erratic flex reading. Moving from chassis to sensor ground fixed it.

[@TurbineResearch]

I’m glad I saw this. I have wired flex fuel sensors with sensor ground and chassis ground with success in both configurations. I have noticed my own car that is chassis grounded will glitch once in a while but it’s never too serious to the point that it changes the fuel multiplier. I have recently been wiring them to sensor ground with no issues either. It’s also hard to find documentation that agrees one way or the other. Seems like it’s 50/50 on what to ground it to. Thanks for the video

[@MonkeyFabGarage]

Noticed this with many sensors. What I did for the flex, is added another 5v dial, that I use in an advanced table for the offsets needed for the E85. So instead of referencing the sometimes unstable flex sensor, I just turn the dial to match the sensor after filling up. Air bubbles issues a thing of the past. Of course, your buddy will barrow the car, fill up on 87 and you’ll hope holleys fuel controls picks up the difference. But hasn’t been an issue yet.

[@SloppyMechanics]

interesting solution! working on some things now that "pause" the input while under power and in boost so it cant change

[@MonkeyFabGarage]

@@SloppyMechanics sorry English is my second language. I meant to say that the flex fuel that I wired in. Not Matt’s. Matt’s is in one of my cars, and is rock solid. The one I wired, gets a bit crazy. So I used a non detent potentiometer. Both read out to my dash (flex and the dial for flex compensation. Fill with gas, adjust knob once and you’re done. Yes it only needs to sample like once an hour. Not 60 times a second.

[@BlaserBuilds]

👍👍👍

[@Conetoe707]

Got any plans to make an electric fan control harness for a holley ecu

[@Stingajp]

Hey Matt. How do I go about getting a dyno tune from you?
5.3 turbo micro pnp 24x btr4. 6sp 93oct and e85 separate tunes.

[@SloppyMechanics]

email in to [e-mail]

[@jimpidala298]

Would this cause it to flash err once in a while it still reads right but flashes sometimes it’s all brand new

[@joeybash4338]

Would that be why mine dont work? I have a gen 1 harness

[@Jfrgarage]

So then do you just leave the sensor ground (white/black in video) out of the connector after moving chassis ground to the other pin?

[@scottadkins918]

My flex harness only has 3 wires. Is this a problem with the 3 wire set up?

[@tommcfadden2226]

Thanks, now I know how to remove those pin connectors. A good video would be to show all the connections Holley uses. JA1 on the Terminator X MAX gave me fits connecting an oil pressure sensor.

[@motoweenies4431]

like how to take them apart and what tools are needed?