Jeep CJ Gauge & Sender Diagnostics - 4x4Wire Complete diagnostics on Jeep CJ gauges and sending units including speedometer, fuel, temperature, oil pressure, and voltage gauges. Jeep CJ Gauge & Sender Diagnostics. Short Cuts: By: John Foutz - 3/2000 CJ Speedometer This article only covers gauges and sending units used in the AMC Jeep CJs built from '72-'86, but some of this I have a 1973 cj5 jeep with a 232 engine. my fuel gauge i have a 1973 cj5 jeep with a232 engine. my fuel gauge and temp gauge were broken. i replaced the entire speedometer assembly way they had it hooked up. the fuel gauge had a green wire from the ign. a white wire to the sending unit also a grey wire . the grey wire was hooked up with the green wire to the same terminal on the fuel gauge