Car Keeps Running After Ignition Turned Off
Having a car that won’t turn off when you remove the key from the ignition or press the Engine Stop button is a strange problem. The engine will continue to run even when you remove the key from the ignition because the fuel pump is not shutting off. A faulty or sticking fuel pump relay or a defective ignition switch typically causes this problem.
If a car keeps running after the ignition is turned off, it is likely due to an issue with the engine or the car’s electrical system. Some common causes include:
- A malfunctioning idle air control valve (IAC) can cause the engine to stay running after the ignition is turned off.
- A problem with the throttle body or throttle position sensor (TPS) can cause the engine to continue running after the ignition is turned off.
- A sticking or worn-out key cylinder or a problem with the starter interlock switch can cause the engine to stay running after the ignition is turned off.
- A fault in the car’s body control module (BCM) or engine control module (ECM) can also cause the engine to stay running after the ignition is turned off.
- A malfunctioning fuel pump relay can keep the engine running after the ignition is turned off.
A certified mechanic must inspect the vehicle to diagnose and repair the issue to prevent potential safety hazards and battery drain. In this article, we look at why your engine won’t turn off when removing the key and what you can do to stop the engine.
Symptoms
- The car keeps running after the ignition turned off
- The car won’t turn off when removing the key.
- The key out of the ignition car still runs.
- Car won’t turn off with key.
- The car keeps running after the ignition is turned off.
- The engine will not stop when you press the Engine Stop button.
How to turn off a car that is still running?
- Do not try to disconnect the battery.
- It is not recommended to start removing random fuses.
- Your car may not restart once you get it turned off. Park the vehicle in a safe location where it ok park.
- Drive your car to a safe location. Remember that your car may not start again after you get it to turn off. So drive it home or to a place that would be ok to leave the car parked.
- Locate the fuse boxes in your car. If you are unsure, look it up in your owner’s manual. Typically there is a fuse box in the engine bay and one on the side of the dashboard. Some models have a fuse box in the trunk as well.
- Determine the fuse and relay for the fuel pump.
- Remove the fuse for the fuel pump or the relay.
- Your car engine dies within 10 seconds.
What to do if the car won’t start?
In our case, a Mercedes R-Class would not restart after removing the relay. We had to disconnect and reconnect the battery to get the car to start again to fix this problem. So far, the problem has not reoccurred. As long as the engine is not running, you can disconnect the battery. This will often reset the module that is not working properly.
Why won’t an engine shut down when I remove the key or press STOP?
Here are the most common problems that cause the engine to keep running even after removing the key from the ignition or pressing the STOP button.
Ignition Module / Keyless Start
The ignition module may fail, or if your car is equipped with an Engine Push to the Start button, the Keyless module could be the culprit. Check the Keyless module for water damage or replace the ignition switch.
Fuel Pump Relay
The fuel pump relay may bind and get stuck in the ON position. It sends power to the fuel pump even when the engine is turned off. Replace the fuel pump reply. Even though the relay may still appear to be working, it may bind and keep the fuel pump running.
Start Stop Button
On vehicles equipped with the Start/Stop convenience feature, the engine may not stop when you press the STOP button. A defective Push Start button can cause this problem. If the button stops working, it may need to be replaced.
Depending on the vehicle, the button may be integrated into the ignition module and may need to be replaced with the module. It is possible to open the ignition module and repair the switch without replacing the module.
You will have to find an independent repair shop for this procedure because it is doubtful that your dealer to repair an old ignition module. If the module has to be replaced, it will require programming and coding, which in most cases, will cost over $1000 for parts and labor.
We hope you find the Car Engine Doesn’t Turn Off When Removing Key or Pressing STOP guide helpful. Check these troubleshooting and repair guides for more help on your vehicle.
Questions?
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