Your engine must be able to hold a steady idle so the car will operate correctly. When an engine stalls at idle it is different from stalling while driving, or if the engine is not starting at all. We are a team of ASE certified mechanics that have created this guide to help you figure out the problem and how to fix it. If you have any questions please ask one of our experts for free.
Engine vacuum is held inside the intake manifold which is a sealed unit, when a vacuum line or intake gasket fails it can create a vacuum leak which will cause the stalling at idle problem. This problem is easy to find because it can make a whistling sound right before the engine stalls. Check out the video below to see how to fix this problem. Please watch this video of the job being done, then continue down the guide to glean additional helpful information.
The throttle bore is used to help regulate the air intake of the engine via the accelerator pedal which is controlled by the driver. When this device becomes dirty at about 70,000 miles it will disrupt the airflow causing the engine to stall at idle. Fortunately, this is an easy problem to fix by cleaning the throttle bore and it only takes about 20 minutes. Check out the video below to show you how the repair is done.
Some older cars (2008 and older) are equipped with an idle air control valve. After about 70,000 miles this valve can get dirty not allowing it's proper operation, again this problem is easy to fix using a simple shop towel and carburetor cleaner and it takes about 20 minutes. Check out the video below of the job being done.
An EGR (exhaust gas recirculation) valve is attached to the engine to help with emission controls. This valve opens when the engine is under load and closes at idle but when the valve malfunctions do a mechanical issue or if carbon gets stuck inside the valve it creates an internal vacuum leak causing a stalling at idle issue. If you are not sure if your car has an EGR or idle control valve, or you are having trouble finding it please ask one of our experts for free. Please watch the video on how to test the valve for problems.
An air intake boot or tube is designed to transfer the engine's air intake from the mass air flow sensor which is monitored by the computer to the throttle bore and into the engine. To check for this problem inspect the air intake tube and boot by running your hands and fingers around the tube to check for cracks or loose hose clamps, or to see if the tube has become disconnected at any point. The video below shows the finding and replacement of an air intake tube.
An automatic transmission vehicle is equipped with a torque converter which is designed to allow the engine to "freewheel" at idle. When this component has a breakdown it can lock up not allowing the engine to run at idle. Usually this first start happens after a freeway drive and will be accompanied by the engine sputtering as the car is coming to a stop, much like a stick shift car does when you forget to push the clutch in. Unfortunately this is not an easy job to fix because the transmission needs to be removed to replace the torque converter which you can watch in the videos below.
If you have a check engine light on that appeared about the same time the engine started to stall at idle, you should run the codes to see what trouble code comes up. This video will show you how to get the codes and guide us in the right direction to fix the problem.
Our certified technicians are ready to answer stalling at idle questions for free. We hope you saved money and learned from this guide. We are creating a full set of car repair guides. Please subscribe to our 2CarPros YouTube channel and check back often for new videos which are uploaded regularly.