Fuel gauge and tachometer gauge not working properly?

Hello,

The fuel gauge is a float that rides on a metal rod in your fuel tank. Over time the rod gets gunked up with stuff from the fuel and the float will no longer be able to move up the rod when you put fuel in your fuel tank. The best way to fix this is to replace the fuel sending unit altogether. The tachometer gets it's signal from the Power-train Control Module (PCM) which gets it's signal from the Vehicle Speed Sensor (VSS) which is on your vehicle's trans-axle.
I have included in the diagrams down below location, test, and removal and installation instructions for both the VSS and Fuel Sending Unit. Go through this information and get back to us with what you find out. The tests will have you use a multi-meter, so if you are unfamiliar with how to use one a have included a link below for you to go to if needed.

https://www.2carpros.com/articles/how-to-use-a-voltmeter

Thanks,
Alex
2CarPros

It could be failed gauge unit. A shop with a scan tool can manipulate the cluster to verify a failure.

Roy

It may be the dash has gone bad as they are digital. They can be rebuilt just make sure everything is ok like coolant temp etc. You can look online of rebuilders.

Hi and thanks for using 2CarPros. Com.

The fuel gauge operates off a sending unit and float in the fuel tank. Often times, the sending unit, which uses a rheostat to send signals to the gauge, fails. Basically, the rheostat fails and needs replaced.

To properly test the system requires a good bit of time and proper tooling. I am going to attach 4 pictures which are the diagnostic flow chart needed to test for the fault. Here are the directions.

FUEL GAGE INACCURATE OR INOPERATIVE

DIAGNOSTIC AIDS
- Ensure that the fuel level is in the same range as the customer concern.
- Refer to Fuel Level Specifications in order to verify the correct fuel level sender readings. The Fuel Level (%) parameter is available on the scan tool in the PCM EVAP data list.

TEST DESCRIPTION
See attached pictures for procedures.
_____________________________________

Let me know if this helps or if you have other questions. I realize it is quite involved.

Take care,
Joe

The float in the fuel tank is what sends the signal to the gauge. It is part of the fuel pump. Therefore, yes, the new pump / float assembly could be faulty.

Hi:
It sounds like there may be a problem with the body control module (BCM). Try disconnecting the battery for around 5 minutes the reconnect. This should reset it if that is the problem. Let me know if it works or if you have other questions.

Joe

Hi:
It sounds like the rheostat is bad on the fuel float. It is part of the fuel pump in the fuel tank. The tank needs removed to check and replace it. As far as the AWD light, have the computer scanned at a nationally recognized parts store. Most will do it for free and it will help identify the problem.

Joe

FUEL LEVEL SENSOR REPLACEMENT

REMOVAL PROCEDURE

Remove the fuel sender assembly.
Disconnect the fuel pump electrical connector (2).
Remove the fuel level sensor electrical connector retaining clip (4).
Disconnect the fuel level sensor electrical connector from under the fuel sender cover (5).
Remove the fuel level sensor retaining clip.
Squeeze the locking tangs and remove the fuel level sensor (3) from the modular fuel sender.

INSTALLATION PROCEDURE

Install the fuel level sensor (3) to the modular fuel sender.
Install the fuel level sensor retaining clip.
Connect the fuel level sensor electrical connector.
Install the fuel level sensor electrical connector retaining clip (4).
Connect the fuel pump electrical connector (2).
Install the fuel sender assembly
Inspect for fuel leaks with the following procedure:
7.1. Turn ON the ignition for 2 seconds .
7.2. Turn OFF the ignition for 10 seconds .
7.3. Turn ON the ignition.
7.4. Inspect for fuel leaks.

https://www.2carpros.com/kpages/auto_repair_manuals_alldata.htm