## Car Engine Stops While Idle: Troubleshooting and Solutions
A car engine that stops while idling is not only annoying but can also be dangerous, especially if it happens in the middle of traffic. If your car is experiencing this problem, there are a few things you can do to troubleshoot and fix the issue.
### Common Causes of Engine Stalling at Idle
* **Idle air control valve (IACV)**: The IACV is responsible for controlling the amount of air that bypasses the throttle valve at idle. If the IACV is faulty, it can cause the engine to stall when the throttle is closed.
* **Throttle position sensor (TPS)**: The TPS sends a signal to the engine control unit (ECU) indicating the position of the throttle valve. If the TPS is faulty, it can send incorrect signals to the ECU, which can cause the engine to stall.
* **Vacuum leaks**: Vacuum leaks can cause the engine to stall by allowing unmetered air to enter the intake manifold. This can lean out the air/fuel mixture and cause the engine to lose power.
* **Fuel pump**: A weak or failing fuel pump can cause the engine to stall by not providing enough fuel to the engine.
* **Fuel filter**: A clogged fuel filter can restrict the flow of fuel to the engine, which can also cause it to stall.
### Troubleshooting Steps
1. **Check the IACV**: The IACV is usually located on the throttle body. You can check it by removing the electrical connector and starting the engine. If the engine idles smoothly, the IACV is likely faulty.
2. **Check the TPS**: The TPS is usually located on the throttle body. You can check it by using a voltmeter to measure the voltage at the sensor’s output terminal. The voltage should change smoothly as you open and close the throttle.
3. **Check for vacuum leaks**: You can check for vacuum leaks by using a smoke machine or by spraying carburetor cleaner around the intake manifold while the engine is running. If the engine speed changes, you have found a vacuum leak.
4. **Check the fuel pump**: You can check the fuel pump by listening for it when you turn the ignition key to the “on” position. You should hear the fuel pump running for a few seconds. If you don’t hear anything, the fuel pump may be faulty.
5. **Check the fuel filter**: The fuel filter is usually located under the car. You can check it by removing it and inspecting it for dirt and debris. If the fuel filter is clogged, it will need to be replaced.
### Solutions
Once you have identified the cause of the engine stalling, you can fix the problem. Here are some common solutions:
* **Clean or replace the IACV**: If the IACV is dirty, you can try cleaning it with carburetor cleaner. If the IACV is faulty, it will need to be replaced.
* **Adjust or replace the TPS**: If the TPS is out of adjustment, you can adjust it using a voltmeter. If the TPS is faulty, it will need to be replaced.
* **Fix vacuum leaks**: Vacuum leaks can be repaired by tightening loose hoses or replacing damaged gaskets.
* **Replace the fuel pump**: If the fuel pump is faulty, it will need to be replaced.
* **Replace the fuel filter**: If the fuel filter is clogged, it will need to be replaced.
If you are not comfortable troubleshooting and fixing the problem yourself, you can take your car to a mechanic. They will be able to diagnose the problem and fix it quickly and efficiently.
