gas gauge not reliable

AKSHUNJ · 02-21-2005, 01:16 PM

Symptoms are as follows;

My gas gauge seems to be sticking on full before it shows any drop in fuel. After about 50 miles it suddenly and quickly drops to below the first 1/4 of a tank and then comes back up slowly to indicate the tank is more than 3/4 full.

The gauge also drops to show a 1/2 tank and then stays there until I go about 170 miles and then it drops down to 1/4 of tank when I get to 200 miles on the trip odometer.

IT stays there until I hit about 250-270 miles at which point it drops to the E mark and I have 3 gallons left.

The only part that is normal is having 3 gallons left on E. It's always done that since day one. The gas gauge used to be very reliable and did not fluctuate at all on inclines and descents or during hard cornering.

I could swear there was a TSB about cleaning some part in the fuel tank that is susceptible to gunk building up on it but I can't find it on all data. Any ideas? Thanks in advance.

Enola Gaia · 02-21-2005, 03:18 PM

Taco OEM fuel gauges are notorious for progressively accelerating their fall as the fuel gets used. They sit on 'Full' for a while, then seem to drop faster and faster. Your description of up-and-down behavior, though, doesn't sound quite so normal.

Don't know about Tacos, but... I seem to recall there was a TSB about 4Runner fuel sender / gauge weirdness during a brief period around 1999 or so....

AKSHUNJ · 02-21-2005, 03:25 PM

THANK YOU! IT was for a 4Runner and that's why I couldn't find it!

Now, anybody have access to the TSB without taking a ride to the stealer?

EL010-99 DEC 99 Instruments - Fuel Gauge Calibration Procedure

sportsman1539 · 02-21-2005, 04:12 PM

mine will still stay on full for a while and then drop normally until i get to 1/4 of a tank. when it gets to a 1/4 tank, it will drop all the way to E and then back up. it moves alot when it gets to 1/4 tank.

Enola Gaia · 02-21-2005, 04:24 PM

Quote:

...Now, anybody have access to the TSB without taking a ride to the stealer?
EL010-99 DEC 99 Instruments - Fuel Gauge Calibration Procedure

If it was issued for a 4Runner, I'm willing to bet you'd have a better chance tracking down its text (if it was ever posted) over at YotaTech. That's where the 4Runner crowd hangs out....

Enola Gaia · 02-21-2005, 04:29 PM

The symptoms and the recalibration portions of the TSB are quoted over at 4X4 Wire:

http://www.4x4wire.com/forums/showth...mp;o=&vc=1

...However, it also states this was only for 4Runners... I have no idea if it applies to Tacos as well...

AKSHUNJ · 02-21-2005, 04:44 PM

Thanks for that link. Reading up on it now I am starting to think the front end of my truck sagging might be causing some of this. I didn't realize the there was a circuit to sense the incline of the truck.

I might try that calibration procedure once I swap the drivers/passengers coilovers around to level the truck. It works for a while before the drivers side starts to sag again.