Key points
- The fuel pump relay is an electrical component that controls the flow of electricity to the fuel pump.
- When you turn the ignition key to the “ON” position, the relay sends power to the fuel pump, which then pumps fuel from the fuel tank to the engine.
- If you suspect that your fuel pump relay is faulty, you can jump it to bypass the relay and allow the fuel pump to run.
A faulty fuel pump relay can leave your car stranded, preventing you from reaching your destination. Learning how to jump fuel pump relay is a crucial skill for any car owner, allowing you to get back on the road quickly and safely. In this comprehensive guide, we will walk you through the step-by-step process of bypassing the fuel pump relay, ensuring that your vehicle receives the necessary fuel to start and run.
What is a Fuel Pump Relay?
The fuel pump relay is an electrical component that controls the flow of electricity to the fuel pump. When you turn the ignition key to the “ON” position, the relay sends power to the fuel pump, which then pumps fuel from the fuel tank to the engine. If the fuel pump relay fails, the fuel pump will not receive power, and your car will not start.
Symptoms of a Faulty Fuel Pump Relay
There are several symptoms that may indicate a faulty fuel pump relay:
- Car won’t start: This is the most common symptom of a bad fuel pump relay. When you turn the ignition key, the engine will crank but not start.
- Fuel pump not running: If you listen closely, you may not hear the fuel pump running when you turn the ignition key to the “ON” position.
- Engine stalls: A faulty fuel pump relay can cause the engine to stall while driving. This is because the fuel pump is not receiving power, and the engine is not getting the fuel it needs to run.
- Loss of power: You may experience a loss of power while driving, as the engine is not getting enough fuel.
How to Jump Fuel Pump Relay
If you suspect that your fuel pump relay is faulty, you can jump it to bypass the relay and allow the fuel pump to run. Here’s how to do it:
1. Safety First: Park your car on a level surface, engage the parking brake, and put the car in park.
2. Locate the Fuel Pump Relay: The fuel pump relay is usually located in the fuse box under the hood of your car. Refer to your vehicle’s owner’s manual for the exact location.
3. Identify the Fuel Pump Relay: The fuel pump relay is typically labeled “Fuel Pump” or “FP.”
4. Remove the Fuel Pump Relay: Using a pair of needle-nose pliers, gently pull the fuel pump relay out of its socket.
5. Jump the Fuel Pump Relay: Use a jumper wire to connect the two terminals on the fuel pump relay socket. The terminals will usually be labeled “85” and “87.”
6. Turn the Ignition Key to “ON”: Turn the ignition key to the “ON” position, but do not start the engine.
7. Listen for the Fuel Pump: You should now hear the fuel pump running. If you don’t hear the fuel pump running, check the connection of the jumper wire.
8. Start the Engine: Once you hear the fuel pump running, start the engine. If the engine starts, the fuel pump relay is faulty and needs to be replaced.
Additional Troubleshooting Tips
- Check the Fuel Pump Fuse: Before jumping the fuel pump relay, check the fuel pump fuse in the fuse box. If the fuse is blown, replace it with a new one of the same amperage.
- Check the Fuel Pump Wiring: Inspect the wiring harness that connects the fuel pump relay to the fuel pump. Look for any loose connections, damaged wires, or corrosion.
- Test the Fuel Pump: If you have access to a fuel pressure gauge, you can test the fuel pressure at the fuel rail. A faulty fuel pump will not be able to generate enough fuel pressure to start the engine.
When to Replace the Fuel Pump Relay
If you have successfully jumped the fuel pump relay and the engine has started, you will need to replace the faulty relay as soon as possible. Driving with a bypassed fuel pump relay can be dangerous, as it can cause the engine to stall while driving.
Final Note
Bypassing the fuel pump relay is a temporary solution that allows you to get your car running again. However, it is important to replace the faulty relay as soon as possible to ensure the safe and reliable operation of your vehicle.
Frequently Discussed Topics
Q: What are the risks of driving with a bypassed fuel pump relay?
A: Driving with a bypassed fuel pump relay can be dangerous, as it can cause the engine to stall while driving. This can lead to accidents, especially if you are driving on a busy road.
Q: Can I drive for a long time with a bypassed fuel pump relay?
A: No, you should not drive for a long time with a bypassed fuel pump relay. The fuel pump relay is an important safety component, and bypassing it can increase the risk of a fire or other problems.
Q: How much does it cost to replace a fuel pump relay?
A: The cost to replace a fuel pump relay can vary depending on the make and model of your car. However, the average cost is between $20 and $60 for the part and labor.