84F15098408

So, my fuel gauge will read full if the tank is entirely full, but slowly drops to Empty and stays there after about 15 miles. My odometer is also jacked up so i've no way to get a MPG reading. Is it the float on the pump in the tank or my gauge cluster? Thanks!

Bill Z

I'm going to guess here. By your description, when you turn on your ignition with a full tank, the gauge shows full but keeping the ignition on and not burning any gas, the gauge goes to empty. Also, your odometer races along at better than 200 MPH. Right off, I'm guessing that you have an electrical problem. Maybe just a ground connection that came loose (maybe not).

Have you or anyone been messing with the electrical system since the last time you noticed everything working OK? Maybe someone installed a radio or something?

calvin

it does sound like a ground problem

84F15098408

Bill, The gauge will read full while i'm driving until about 15 miles down the road it will slowly drop..it doesn't drop while it's just sitting. I found a new problem today as well. When i use my turn signal, my BRAKE warning light comes on instead of the signal. still thinking ground problem? i know nothing about electrical stuff so any help would be appreciated.

Thanks


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Bill Z

I've seen in the past where a fuse was blown and the electricity had to find another path through nearby circuits (this is the simple explanation).

I've also seen fuses that looked good but didn't work.

If you haven't yet, check all of your fuses with a continuity checker (just to make sure).

I've also seen where one of the dual element turn signal and stop light bulbs had one of the elements break and fall against the other element causing an additional circuit which caused weird problems.

With all of this mentioned, let me suggest an idea. Maybe it will work for you. Just remove all of your fuses at one time. Have them all out. I don't have a wiring diagram of your truck so you will have to work this out. Put back in just the fuse that will enable your dash interments (not the illumination lights). Now test drive the truck to see if the gauge stays correct. If it doesn't work correctly, then the problem is in that circuit. If it does work correctly, then the problem is in another fused circuit. Just add back the fuses one at a time until the gauge quits.

Good luck and let me know what happens.