So my fuel gauge (or the sender) is on crack. When I fill up completely, it reads dead empty, but after about 50 miles of driving it SEEMS to read correctly but floats all over the place. Question is how do I check the gauge and sender?

 

i would guess you might have a wiring issue possibly a bad ground connection. the thing that sucks about trying to track down any issue related to the gas gauge acting funny will end up with someone dropping the gas tank to find it. i guess since you don't have to deal with rust where you are that should be not to big of an issue once the gas tank is near empty.

 

Yeah, no rust here. So how is the wiring connected on the back of the gauges? Is it individual or a big plug to the whole set of gauges? And can one get their hands above the tank to check it's connections? Without removal of the tank?

 

2 plugs on the back of the instrument cluster. i don't think you can get at it without dropping the tank or removing the box unless yo have a body lift.
this is for a 93 but i think it should be the same for a 91

 

Mine has been on the fritz also. When I fill the tank, it pegs full, but it goes down to empty within 10-15 gallons (30 gal tank), and stays there, so I watch the miles. I had to drop the tank when I did my new leaf spring swap, so I cleaned the tank out and dropped in a new fuel pump/filter/sending unit. No change to the way the fuel gauge works . I looked the wiring over before I strapped the tank back up, and saw nothing obvious, and the plug/harness seemed okay. It's a tight fit, but I can get my hand back to the top of the tank (having the 4" lift allows me to move around there a little easier). Good luck, and if you find an answer, please post back.

 

I will. It isn't a huge priority right now but at some point I will get to it!

 

Mine was doing the same thing. I dropped the tank and found that the float had a hole in it and had sank. Replaced the float and it's working perfectly.

 

My old Mazda PU had a door in the bed over the fuel pump.
I cut a door in the floor of my 92 E-150 over the pump, and may well cut one in the bed on my 87 Ram...
Makes life ever so much easier.

 

My Cummins has the same problem. I have had so many vehicles that have a non working fuel gauge that I don't really notice it. My daily driven 95 dakota has no fuel or oil pressure gauge reading haha.

 

bed comes off easy 6 bolts filler neck and unplug the back wireing while its off give the frame a good wire brushing and paint took my bed off buy my self with a engine hoist