after I pull the tank, replace the sensor, is there a way to test it outside of putting it back together, adding gas and crossing my fingers?
You don't have to pull the tank to remove the fuel sending unit (unless you have some different sort of tank. Just lay on the ground, and look at the driver side of the tank. You will see the sending unit, right there. Take a flat head screw driver and a hammer, and tap the lock ring counter clockwise and remove the sending unit. :Handshake
USe something soft to remove the ring like a brass drift. It avoids sparks. You can operate the sender outside of the tank plugged in and watch the fuel gauge.
OK, stupid question but since I've never done this before, and I'm playing with gasoline, I would assume that it is better to remove the sending unit on an empty tank of gas?
Don't worry, I work in oil field explosives. I'm always careful about things that go BOOM! Would the best way be to pull the fuel line at the fuel pump and drain the gas there?
You won't get any gas out at that location, except for what ever miniscule amount that is in the fuel pump and/or the fuel line. If the car is out of fuel, of course, it will have some in the tank. You can drive the driver side of your car up on two car ramps(one for the front tire and one for the rear tire) to roll what gas there is in the tank to the passenger side. Just have a catch basin on hand to catch what ever might come out of the tank when you break the seal on the sending unit. If your car is low enough, you shouldn't get hardly any. If you have too much gas in your vehicle to for that method, you will have to siphon it out into gas jugs. You can pick up a hand siphon pump for a few dollars, like the ones used for the portable kerosene heaters. They work good. Stick a piece of hose on the hose, that is already on the pump, to lengthen it enough to reach the gas in the tank.
OK, here's a real twist for you! I pulled the fuel tank and removed the fuel sensor and the gas vapor return plug. Gave it a couple of days to air out and then stuck my eye in with a flash light and found a huge curled flake of some sort of silver paint. It seems that the previous owner had replaced the sensor and vapor return and used this silver paint as some sort of sealant. He apparently used so much that it leaked down into the tank and then curled and then solidified. (see photo). It was about the size of a waffle and at the exact spot where the float would be so I believe that it was the reason my fuel gauge always showed full. I had to break the paint apart to get it out of the tank and I still need to get out any smaller bits before I can reassemble it. I've decided that since I have the tank out, I'll sand blast it and then treat it for rust and seal it. Now how's that for one weird problem/solution? Oh yeah, also found a little yellow filter of some sort. Any ideas what it is and should it be floating around in my tank?
OK, now what do I do? If you've been following this thread, then you know everything that I've already done to fix this problem. Quick recap: Fuel gauge goes up and down with no problem. But when power is on, it shows only full. Fuel sensor has power. Removed tank and sensor to find that the tank had a bunch of junk in it that I assumed was jamming the float of the sensor. So tonight I hooked up the sensor to test it (outside of the tank) and once again, once the power is turned on, it shows a full tank, no matter where the float is. The fuel sensor appears to be new. Could I have a bad sensor? I'd hate to spend $75 just to have the same problem. IDEAS? HELP?
If I check the ohms on the sensor and then adjust the bobber up and down, there should a change right? and if not, then the fuel sending unit is toast?
Yes. Should be around 73ohms empty (float down) and around 10 ohms full (float up). Be sure to check the resistance (ohms) with all of the wires disconnected. bobber = float.
OK, I made this little video of me testing my fuel sender. As I have never done this before, can anyone tell me if I'm doing it wrong? It would seem from everything that I've been told, that this unit is not working properly.
I got tired of dealing with mine and just bought a new sending unit from autokrafters for $89.99. Mine would work out of the gas tank but not in the gas tank. Go figure.
