Ameer Randolph
The fuel pump in a car is powered by a switch that receives 12V when the engine's oil pressure is built up. This switch can short out, especially if it's still the original switch from the 1980s. If the fuel pump continues to run after the car has shut off, it could be due to a sticking relay or a shorted switch.
| Characteristics | Values |
|---|---|
| Fuel pump relay stays on | Can cause the vehicle to stall while operating and result in a crash |
| Fuel pump continues to run after cars shut off | Can be caused by a sticking relay |
| Fuel pump shuts off | Can be caused by turning the key without starting the car |
| Fuel pump continues to run after cars shut off | Can be caused by a switch shorts out |
What You'll Learn
Fuel pump relay stays on
The fuel pump has a backup power circuit through the FPOP switch (Fuel Pump Oil Pressure). When the engine builds up oil pressure, this switch sends 12V to the fuel pump. It's common that the switch shorts out, especially if it's still the original switch from the 1980s. Depending on your model year, the switch will be either above the oil filter (newer blocks) or on the top of the block, driver side, just behind the intake (older blocks). Disconnect that switch and if the fuel pump stops running, that's your problem.
The fuel pump relay can stick closed, causing the fuel pump to run continuously. The problem can happen in circuits that supply power to the fuel pump fuse at all times. In such a scenario, you’ll hear the fuel pump running continuously, even when the key is out of the ignition. On some vehicles, the engine computer, which is often referred to as the powertrain control module (PCM), monitors the fuel pump relay and its circuit. If the PCM detects a problem, it turns on the check engine light and stores a corresponding diagnostic trouble code (DTC) in its memory.
If the fuel pump relay stays on, you can tap on it with a screwdriver or something. If that does NOT stop the fuel pump, you might have a sticking relay. When you shut off the car, pop the hood, locate the relay (on the firewall, by the brake booster) and tap on it with a screwdriver or something.
If you have a 3 wire oil pressure sending unit, by design, it will bypass a bad fuel pump relay once pressure builds, if that bypass switch in the sender is bad, it can turn on your fuel pump without oil pressure.
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Shorting of the fuel pump switch
The fuel pump has a backup power circuit through the FPOP switch (Fuel Pump Oil Pressure). When the engine builds up oil pressure, this switch sends 12V to the fuel pump. It's common that the switch shorts out, especially if it's still the original switch from the 1980s. Depending on your model year, the switch will be either above the oil filter (newer blocks) or on the top of the block, driver side, just behind the intake (older blocks). Disconnect that switch and if the fuel pump stops running, that's your problem.
The fuel pump relay can stay on and shut off causing the vehicle to stall while operating and resulting in a crash. When you shut off the car, pop the hood, locate the relay (on the firewall, by the brake booster) and tap on it with a screwdriver or something.
Leaks in the cooling system will cause the vehicle to overheat, and experience other problems.
Brake lights don't work when I brake or reverse.
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Sticking fuel pump relay
If you have a sticking fuel pump relay, it can cause your car to sputter and shut off. When you shut off the car, pop the hood and locate the relay (on the firewall, by the brake booster). Tap on it with a screwdriver or something. If that does not stop the fuel pump, you might have a sticking relay.
The fuel pump has a backup power circuit through the FPOP switch (Fuel Pump Oil Pressure). When the engine builds up oil pressure, this switch sends 12V to the fuel pump. It's common that the switch shorts out, especially if it's still the original switch from the 1980s. Depending on your model year, the switch will be either above the oil filter (newer blocks) or on the top of the block, driver side, just behind the intake (older blocks). Disconnect that switch and if the fuel pump stops running, that's your problem.
The fuel pump relay can stay on but in some cases, it can shut off causing the vehicle to stall while operating and resulting in a crash! Do be careful out there guys!
If you have a sticking fuel pump relay, it can cause your car to sputter and shut off. When you shut off the car, pop the hood and locate the relay (on the firewall, by the brake booster). Tap on it with a screwdriver or something. If that does not stop the fuel pump, you might have a sticking relay.
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Fuel pump continues to run
If your fuel pump continues to run after you shut off your car, you might have a sticking relay. When you shut off the car, pop the hood, locate the relay (on the firewall, by the brake booster) and tap on it with a screwdriver or something.
If that does not stop the fuel pump, you might have a shorted switch. The fuel pump has a backup power circuit through the FPOP switch (Fuel Pump Oil Pressure). When the engine builds up oil pressure, this switch sends 12V to the fuel pump. It's common that the switch shorts out, especially if it's still the original switch from the 1980s. Depending on your model year, the switch will be either above the oil filter (newer blocks) or on the top of the block, driver side, just behind the intake (older blocks). Disconnect that switch and if the fuel pump stops running, that's your problem.
The fuel pump relay can also stay on and in some cases, it can shut off causing the vehicle to stall while operating and resulting in a crash.
If you are still having trouble, you might want to seek help from a professional technician.
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Recall for 2011-2013 Jeep Grand Cherokees
The fuel pump relay inside the TIPM-7 may fail, causing the vehicle to stall without warning. Chrysler (FCA US LLC) is recalling certain 2011-2013 Dodge Durango and Jeep Grand Cherokee vehicles equipped with a 3.6, 5.7, or 6.4 liter engine and previously recalled under NHTSA Recall 14V530 or 15V115.
The fuel pump relay wiring may fail, causing the vehicle to either fail to start or stall out. Dealer feedback suggested that some fuel pump relays containing silicon deposits were interrupting electrical currents.
The remedy for this recall is still under development. Interim notices informing owners of the safety risk will be mailed beginning January 3, 2020. Vehicles that experience a fuel pump failure will receive an interim repair.
If the fuel pump does not stop running, you might have a sticking relay. When you shut off the car, pop the hood, locate the relay (on the firewall, by the brake booster) and tap on it with a screwdriver or something.
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Frequently asked questions
Yes, a faulty fuel pump can cause a car to shut off. A fuel pump relay can stay on after the car is turned off, causing the vehicle to stall while operating and resulting in a crash.
The fuel pump has a backup power circuit through the FPOP switch (Fuel Pump Oil Pressure). When the engine builds up oil pressure, this switch sends 12V to the fuel pump.
Pop the hood and locate the relay (on the firewall, by the brake booster). Tap on it with a screwdriver or something. If the fuel pump still doesn't stop running, you might have a sticking relay.
