Hey guys...I got an '87 B II with the 2.9 v6, 4x4, 5 spd manual. My gas gauge works fine for the first half tank...but the second half it starts going down and going back up. Sometimes it will even drop down below the "E".

Any ideas? Can it be a quick fix?

Thanks in advance!

--Ryan--

 

That's typical. Mine does it as well. The "quick fix" is to calculate how far you go on a full tank and use your trip odometer to gauge how much fuel you have. The best thing to do is to go ahead and drop the tank and put in a new float / sending unit. These things are notorious for 1/2 tank-to-empty fluctuation issues. You can start out, though, by checking your wiring to see if it's got good connections to see if that's part of it or not (another typical issue with the float and in-tank pump). Hope this helps.

 

How would one go about checking those things? How dificult is it to drop the tank.

In my '67 F-100 the tank is behind the seat and everything is accessable. Im not sure about this one.......

I use the trip meter now and i get around 100-115 mile so a quarter tank..but its just nice to see it on the gauge.

 

Dropping the tank isn't difficult, per se, but you would want to do it with the tank empty, IMO. It's just a matter of unbolting the skid plate and then loosening the tank straps, after you've disconnected the fuel lines, filler tube, etc., of course. I would suggest having a floor jack or at least one other set of hands handy, though. Your in-tank fuel pump / sender stuff is on top of the tank, and the wiring goes along the driver's side, IIRC. There is only so much room to reach up and feel around to check the connections, etc. Some people cut an access hole in the deck of the cargo area to access it vice dropping the tank. You're getting about the right amount of mpg per quarter tank to figure in 375-425 miles per tank. I have actually gotten 475 miles out of a tank of gas in mine, but that was mostly open road driving with the cruise control being utilized. I hear ya about wanting to see it on the gauge, but I'm so used to using the trip odometer and have figured a few tricks on getting the gauge to be a little more friendly at times. My '86 Ranger was just as bad (actually worse, sometimes!), though. It would hover at 1/2 a tank for a while, then drop to damn near empty... and I'd go fill it up, and would probably put around half a tank of gas in. At least I never had to worry about not having fresh gas in it! For more info, check this out:

Autozone.com Repair Guide - Fuel System

 

Ya, that will help alot. Thanks for all the helpful info! I graduate on saturday...so i will be having some free time.