Fuel consumption signal
Posted: Thu Jul 29, 2021 1:29 pm
Hi!
I am researching trying to figure out if I should buy the UT-comp pro and associated sensors or not. I have a Subaru impreza wrx sti 2008. It's a family mobile and a street car so any modifications have to retain original functionality to 110 percent. The ECU is very programmable and support everything from flex fuel sensors to bigger injectors etc. I like the idea of the ut-comp very much as I can see a lot of parameters that the ECU cant see like EGTs, continous oil pressure, potentially transmission temps etc.
I like the idea of a display as well. Despite having an android stereo and possibility to run info through there, I want a display for when I play music or have naviagtion up on the screen. This require me to use the only space available which is where the clock/outside temp/fuel consumption display lives today. Modifying this space to fit the 3.2 display is not a problem and will look OEM but it will obscure the old display. All the OEM functionality has to stay - I am quite adamant about this so my idea is to move the data to the new display.
Clock - not a problem, outside temp - not a problem, fuel consumption... problem. There is a fuel consumption signal to the clock micro computer today but it comes via can bus from the instrument cluster (of all locations) who presumably gets injector signals from the ECU via can bus. The UT-comp doesn't do can bus from what I have understood so my thought was to use injector triggers but when I read the wiring diagram they are controlled by the ECU by switching the earths. If I splice into the wires it will be a constant 12V so completely useless (and I didn't really like the idea of altering the impedance in that circuit anyway no matter how insignificantly).
Is there something that I can use to read the magnetic field surrounding the injector leads (like an amp-meter or timing light does) and maybe amplify that signal to the UT-comp? I used my best google fu but came up empty handed.
I am researching trying to figure out if I should buy the UT-comp pro and associated sensors or not. I have a Subaru impreza wrx sti 2008. It's a family mobile and a street car so any modifications have to retain original functionality to 110 percent. The ECU is very programmable and support everything from flex fuel sensors to bigger injectors etc. I like the idea of the ut-comp very much as I can see a lot of parameters that the ECU cant see like EGTs, continous oil pressure, potentially transmission temps etc.
I like the idea of a display as well. Despite having an android stereo and possibility to run info through there, I want a display for when I play music or have naviagtion up on the screen. This require me to use the only space available which is where the clock/outside temp/fuel consumption display lives today. Modifying this space to fit the 3.2 display is not a problem and will look OEM but it will obscure the old display. All the OEM functionality has to stay - I am quite adamant about this so my idea is to move the data to the new display.
Clock - not a problem, outside temp - not a problem, fuel consumption... problem. There is a fuel consumption signal to the clock micro computer today but it comes via can bus from the instrument cluster (of all locations) who presumably gets injector signals from the ECU via can bus. The UT-comp doesn't do can bus from what I have understood so my thought was to use injector triggers but when I read the wiring diagram they are controlled by the ECU by switching the earths. If I splice into the wires it will be a constant 12V so completely useless (and I didn't really like the idea of altering the impedance in that circuit anyway no matter how insignificantly).
Is there something that I can use to read the magnetic field surrounding the injector leads (like an amp-meter or timing light does) and maybe amplify that signal to the UT-comp? I used my best google fu but came up empty handed.
