How to Troubleshoot a Car Stalling at Intersections

There's almost nothing worse than having your car stall while you are idling at an intersection. The light turns green and cars behind you start honking. In troubleshooting a car that is stalling at intersections, you can do some simple things. Follow these steps to remedy the problem yourself, although it may be something more serious and you will have to take the car to a mechanic.

Difficulty: Moderate

Instructions

Things You'll Need:

• Wrench set
• Pliers
• Screwdrivers of various kinds
• New air filter
• New fuel filter
• Fuel injector cleaner
• Carburetor cleaner
• Spark plugs
• New plug wires

1. Check the air filter to ensure it is clean. Clean or replace as needed.

2. Change the fuel filter. A clogged fuel filter will not allow enough fuel to reach the engine.
   

3. Look for vacuum hoses that are detached from their ports.

4. Crawl under the car with a small, clean metal container and loosen the fuel line where it exits the tank. Check for rust and sediment.

5. Clean the carburetor on older cars or the fuel injectors if it is a fuel-injected car. Ensure the fuel pump is working properly.

6. Adjust the idle speed by turning the idle setscrew on older cars. This screw is normally located near the base of the carburetor. Turning the screw clockwise will cause the car to idle faster.

7. Install new spark plugs or remove, clean and reinstall the current ones. Check the spark plug wires for cracks or looseness. Ask your mechanic to check the electronic spark control module.

8. Suspect a faulty throttle position sensor on a fuel-injected car and have it checked by your mechanic if none of the above steps remedies the problem.

Tips & Warnings

• Always shut off your engine before working on your car.
• Always properly support your car on jack stands and block the wheels before crawling under it.
• Remove the positive battery cable from the terminal before attempting any electrical system repairs on cars.
• Never allow a source of ignition near the battery or fuel system components.
• Use a metal container placed on the ground to collect gasoline as you check for sediment because it is self-grounding. Use of a plastic container may result in a spark and a fire.