Edmunds Answers



  • zaken 11/06/13 1:56 pm PST

    This could be caused by several different issues. It might be poor ground connections from the battery to the engine; and from the battery to the chassis; or it could be poor grounding of the instrument panel; or it could be a defective fuel level sensor in the gas tank; or it could be a defective fuel gauge; or it could be poor contact in the wiring plugs between the instrument panel and the fuel level sensor in the gas tank; or a poor ground connection from the gas tank to the chassis.

    In order to fix this problem; you'll need a good quality digital multimeter, a wiring diagram for this vehicle, and a clear understanding of how to troubleshoot electrical circuits by voltage drop testing.

    You can get a wiring diagram from a service manual for this vehicle; either in your local library; or by buying a Haynes or Chilton service manual at a local auto parts store or online.

    I would recommend starting by making sure that the battery ground post has two ground leads connected to it; one being the heavy ground cable which should be attached to a bolt that threads directly into the engine. The ground cable cannot be connected to a bracket, or a painted part, or a part that is not made of metal. The second ground lead from the battery should be connected to a nearby clean bolt that threads into the fender. All electrical connections should be polished with a file until they are shiny, on all the cntact surfaces.

    When the original ground cable is replaced; the replacement cable often will not have a second ground wire attached. In this situation; a second ground wire must be added. It can be made from a length of 12 gauge stranded electrical wire; with suitably sized ring terminals crimped to the ends; after the insulation at the ends has been stripped off. This wire can be placed on the bolt that tightens the cable clamp; under the nut.

    There should also be a dedicated ground wire from a bolt in the engine to a bolt in the firewall. This wire can be fabricated from bult wire and ring terminals if needed. These 2 auxiliary ground cables are essential for proper operation of the electrical system.

    I would also locate the ground wire from the fuel tank; and make sure it has not been disconnected or damaged. It is always good practice to disconnect the ground bolt, and thoroughly clean all the wire termnals and the bolt.

    If you need additional information; click the "answer this question" button below this message; type your message in the box that appears, and click the "submit answer" button. Please include your postal zip code if you'd like a referral to a good local shop to do this work. Thank you.


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