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On some vehicles, a sensor connected to a floater, much like the one in your toilet, measures the level of fuel in the tank based on its position. Similar to an electric slot-car track, the resistance of electricity in the lever determines the speed, or in this case, the level of fuel. So, what happens is, the resistance of electricity moves the guage on your dashboard in a near-accurate ratio with the level of gas in your tank. In your case, it appears the wires are connected backwards due to one of three problems - a factory fault, bad grounding in your dashboard, or crossed wires in your guage assembly connectors (check both ends). If your vehicle still has a warranty on it, you might want to take the dealer up on this one and claim you don't understand anything about cars (if you modified any of the vehicle's systems in any way). Else, a fuel pump, wiring correction and testing, and reassembly of your fuel system could cost upward of $600 at some shops. Typical dealer costs range around the $450 area, but an hour of your time, a multimeter, and about a gallon of idled fuel, you can figure this one out on your own. OEM (Original Equipment Manufacturer) fuel pumps costs anywhere from $69 to $200 depending on your vehicle, application, and equipment arrangement because some fuel pumps are actually inside the gas tank! This is something anyone would need to know first; prior to disassembling a fuel system and wasting a cartoon-filled Saturday morning! Josh Sugar Land, TX

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โˆ™ 2005-03-01 19:35:05
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Q: Why would a 99 4Runner fuel gauge read empty when full then flip when the fuel level goes down?
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Related questions

Why does Gas gauge read empty at full and full at empty?

I would assume that the wires are hooked up backwards

Would it be correct to write My gas gauge read E?

It would be better to write: My gas gauge reads empty. Note that 'gauge' is singular, so it needs the singular verb, reads. If you had several cars all with gas gauges that read empty, then the verb would be read.

Why would a gas gauge jump around and most of time read empty?

Fuel level sender (in tank) faulty. If replacement doesn't correct fault, check sender wiring back to instrument for poor connection. Finally, replace gauge.

Why would the fuel gauge slowly go to empty when you apply the brakes?

Because the gas in being forced to one side of the tank and the sensor that reads the fuel level is reading a lower level as gas gets sloshed around.

What would make your fuel gauge move?

On a car, there is a float inside your gas tank. It is attached to a switch that sends the empty.....full signals to your fuel gauge.

Why would the gauge read empty when the gas tank is half full?

Most Likly a fuel sender problem

Need to know if there is a fuse or for fuel level gauge reads correct level but goes back to empty every couple mins then back to correct level and where would it be located?

You must have a 1998 or newer truck. There is no FUSE for the fuel level gauge. Now there is a fuel leveling sensor on the sending unit that is inside of the fuel tank and that is what controls your fuel gauge. It is common for the sensor to get coated with suffler that is in today's fuels / Gas. You will have to remove the FUEL LEVELING SENSOR That's in the fuel tank and REPLACE it with a new one from the Chevy dealer.

Why would your gas gauge be on quarter tank but really be empty?

The fuel sensor in the gas tank is bad and needs replaced.

What would cause the fuel gauge on a 84 camaro to read full then drop to empty?

Faulty signal sender in the tank.

Why would a 1990 Mazda rx7 convertible manual begin to stutter and stall when the gas tank gets to the 12 full level?

your fuel gauge is probably bad. You are probably empty when it says 1/2 full.

Why would fuel gauge read empty when the tank is full on a 1997 Buick Park Avenue Ultra?

have an experience mechanic test you fuel pump fuel level sensor, which is part of the fuel pump, ground the wires and if the gauge pecks gauge is good. if it don't you have to replace your cluster which is a seal item and must be replaced as a unit. do not try this yourself.

Is there a chemical that would unstick your Nissan fuel tank gauge?

There is none. But you can try disconnecting the wiring attached to the fuel sending unit and look at the fuel gauge. If it is giving you an empty reading, the fuel gauge is faulty and should be replaced.

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