If you are experiencing issues with your 1990 Ford F150 fuel pump, it may be due to a wiring problem. Wiring issues can be frustrating to diagnose and fix, but with the proper knowledge and tools, you can get your truck back on the road in no time. In this article, we will provide a detailed diagram of the fuel pump wiring for the 1990 Ford F150, as well as some troubleshooting tips and frequently asked questions.
Fuel Pump Wiring Diagram
The fuel pump wiring diagram for the 1990 Ford F150 is a simple circuit consisting of a power wire, a grounding wire, and a fuel pump relay. The wiring diagram can be found on the inside of the fuse box lid, or in the vehicle’s owner manual. The diagram will show you which color wire is which, and where they are located within the circuit.
The power wire for the fuel pump is typically colored red or pink, and is connected to a fuse that is labeled “Fuel Pump.” The grounding wire is typically colored black or brown, and is typically connected to the frame of the vehicle or to the negative battery terminal.
The fuel pump relay is typically located in the engine compartment, and is often labeled as “Fuel Pump” or “FP.” The relay is responsible for sending power to the fuel pump when the engine is running, and for cutting power to the fuel pump when the engine is not running.
| Wire Color | Description |
|---|---|
| Red or Pink | Power wire for the fuel pump |
| Black or Brown | Grounding wire for the fuel pump |
| N/A | Fuel pump relay |
Troubleshooting Tips
If you are experiencing issues with your fuel pump, there are a few things you can check before replacing the entire pump. Here are some troubleshooting tips:
Check the Fuel Pump Fuse
The first thing you should check is the fuel pump fuse. If the fuse is blown, the fuel pump will not receive power and will not work. The fuel pump fuse is typically located in the engine compartment, and is labeled “Fuel Pump” or “FP.” If the fuse is blown, replace it with a new one of the same amperage rating.
Check the Fuel Pump Relay
If the fuel pump fuse is not the issue, the next thing to check is the fuel pump relay. The relay is responsible for sending power to the fuel pump when the engine is running, and for cutting power to the fuel pump when the engine is not running. If the relay is not working properly, the fuel pump will not receive power and will not work.
You can test the fuel pump relay by using a multimeter to check for continuity between the relay terminals. If there is no continuity, replace the relay with a new one.
Check the Fuel Pump Wiring
If the fuel pump fuse and relay are not the issue, the next thing to check is the fuel pump wiring. Check to make sure that all of the wires are connected properly and that there are no breaks in the wiring.
You can test the wiring by using a multimeter to check for continuity between the wires. If there is no continuity, there may be a break in the wiring that needs to be repaired.
Check the Fuel Pump
If all of the above troubleshooting steps do not solve the issue, the final thing to check is the fuel pump itself. The fuel pump may need to be replaced if it is not working properly, or if there is a clog or blockage in the fuel lines.
Frequently Asked Questions
What size is the fuel pump fuse for a 1990 Ford F150?
The fuel pump fuse for a 1990 Ford F150 is typically a 20 amp fuse.
Where is the fuel pump relay located on a 1990 Ford F150?
The fuel pump relay is typically located in the engine compartment, near the battery.
What should I do if my fuel pump is working, but my truck still won’t start?
If your fuel pump is working properly, but your truck still won’t start, there may be an issue with the spark plugs, ignition system, or other components. It is best to have a professional mechanic diagnose and fix the issue.
Can I replace the fuel pump in my 1990 Ford F150 myself?
Replacing the fuel pump in your 1990 Ford F150 can be a challenging task, and requires some mechanical knowledge and experience. If you are not comfortable performing this task yourself, it is best to have a professional mechanic perform the work.
How much does it cost to replace the fuel pump in a 1990 Ford F150?
The cost of replacing the fuel pump in a 1990 Ford F150 can vary depending on the mechanic and the location. On average, the cost can range from $500 to $800.
Conclusion
The fuel pump wiring diagram for the 1990 Ford F150 is a simple circuit consisting of a power wire, a grounding wire, and a fuel pump relay. If you are experiencing issues with your fuel pump, there are a few things you can check before replacing the entire pump. Remember to always exercise caution when performing any repairs or troubleshooting on your vehicle, and if you are not comfortable performing the work yourself, it is best to have a professional mechanic perform the work.
