Re: How to use ohm meter on fuel sender
It can read most anything unless one end of the sender wire is disconnected. There must be no other resistive elements in series or parallel with a device on which you are trying to measure resistance. So yes -- you set the meter to read 33 - 240 ohms. You 1) disconnect the pink wire from the threaded fuel sender terminal. 2) Place place the positive meter lead on the sender terminal and the negative lead on the metal shell of the sender. Depending on where the float arm is will determine what the meter reads. 240 ohms empty, 109 ohms half full and 33 ohms full. Slight variation in the numbers is ok. Constant readings, no readings, or erratic or widly incorrect readings means you need a new sender.
To test the gauge you turn the key on, MOMENTARILY jump the "S" terminal to ground. The needle should peg full. If not, verify there is +12 volts on the "I" terminal and that ther is a good ground. The system cannot work unless there is. When installed in the tank the fuel sender shell must be grounded as well.