Fuel gauge pinned on full but some times seems to work. anyone have any idea where to start to solve this problem?
May 18, 2020 at 10:29 AM
Intermittent fuel gauge stuck on full
1987 FORD F-150
J GOWE
- MEMBER
- 6 POSTS
Advertisement
Do you have dual tanks and I assume if you do then both tanks make no difference?
If so, I attached the wiring diagrams. We need to test voltage coming from the selector switch. You have a number of inline connectors that could cause an intermittent issue. However, the always being on full indicates a short to power. Basically this gauge works off of voltage. The more fuel the higher the voltage which raises the gauge.
Let me know if you have questions. Thanks
If so, I attached the wiring diagrams. We need to test voltage coming from the selector switch. You have a number of inline connectors that could cause an intermittent issue. However, the always being on full indicates a short to power. Basically this gauge works off of voltage. The more fuel the higher the voltage which raises the gauge.
Let me know if you have questions. Thanks
Images (Click to enlarge)
Professional Diagram for 2CarPros Members
Click here to log in and view diagram.
Click here to log in and view diagram.
Professional Diagram for 2CarPros Members
Click here to log in and view diagram.
Click here to log in and view diagram.
May 18, 2020 at 10:59 AM
We do have dual tanks. We don't use the back tank it is fouled. we only had the truck a week and she sat for 6 years.
May 18, 2020 at 11:26 AM
Okay. Then let's treat it like a single tank. Check voltage on the yellow wire with the key on and see what it is telling you. If it is battery voltage then I suspect the fuel gauge sender has failed. Let me know if you have questions. Thanks
May 19, 2020 at 9:53 AM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.