The easiest way to troubleshoot the fuel gauge is to disconnect the gauge and check the sending unit and gauge separately. To do this, disconnect the sending unit from the gauge by unplugging the tail light harness from the mid-body harness. There should be a connector in the trunk, up around the left wheel well. This will isolate the fuel gauge from the sending unit, allowing you to check each one. Working with the tail-light harness, measure the resistance of the tan wire to ground with the fuel tank full of gas. The reading should be 90 Ohms or slightly higher. If the reading is low, then there is a problem with the sending unit, check that the float is free to move up all the way. If you are reading around 65 to 70 Ohms, the gauge will read half full (lower resistance = less gas). If this checks out correctly (around 90 Ohms) then check the fuel gauge, I use two 50 Ohm 5W resistors (easily obtained at the local electronics parts outlet). Go back to the trunk, and with the tail-light harness disconnected, place a 50 Ohm resistor from the tan wire in the mid-body harness to ground, turn the ignition switch to on, the reading should be just above half tank. Now connect the two resistors in series, so that you have 100 Ohms. Connect the 100 Ohm string between the tan body harness wire to ground, the gauge should read just above full.
  • No new posts General Discussion
    General off-topic banter. No religious, political or technical discussion.
    3018 Topics
    3121 Posts
    Last post by dvdgetd3 View the latest post
    Tue Feb 20, 2018 8:03 am
  • No new posts Engine / Transmission / Rearend
    Engine, ignition, fuel, cooling, exhaust, clutch, transmission, rear axle
    109 Topics
    214 Posts
    Last post by Ds67cutty View the latest post
    Mon Feb 19, 2018 3:41 pm
  • No new posts Suspension / Steering / Brakes
    Suspension, steering, brakes, wheels & tires
    41 Topics
    59 Posts
    Last post by yuanyuan View the latest post
    Wed Feb 07, 2018 9:05 am
  • No new posts Electrical and Wiring
    Charging, starting, lighting, gauges, HVAC
    806 Topics
    833 Posts
    Last post by yuanyuan View the latest post
    Wed Feb 07, 2018 8:13 am
  • No new posts Interior
    Inside the car...appearance, repair, upgrades
    51 Topics
    101 Posts
    Last post by yuanyuan View the latest post
    Wed Feb 07, 2018 7:43 am
  • No new posts Body & Paint
    Sheetmetal, frame and paint
    49 Topics
    76 Posts
    Last post by yuanyuan View the latest post
    Wed Feb 07, 2018 9:16 am
  • No new posts Shop & Tools
    Discuss your workshop and related equipment
    9 Topics
    9 Posts
    Last post by CalebZach View the latest post
    Thu Jul 27, 2017 8:42 am
  • No new posts Project Updates
    Post progress reports on your project car(s)
    19 Topics
    86 Posts
    Last post by chenjianwei View the latest post
    Mon Feb 05, 2018 7:54 am

  • In total there are 10 users online :: 0 registered, 0 hidden and 10 guests
    Most users ever online was 172 on Sat Nov 17, 2012 2:39 pm
    Registered users: No registered users

    Legend: Administrators, Global moderators
  • Statistics
  • Total posts 5311 • Total topics 4621 • Total images 204 • Total members 628
    Our newest member brcsparks