What Causes Engine Stalling at Idle Speed?
2 Answers
There are many reasons that can cause unstable idle speed and frequent stalling in a car, such as air intake system leaks, low fuel pressure, clogged air filters, injector atomization leaks, improper idle adjustment, faulty spark plugs, air flow meter malfunctions, etc. Below is an introduction to idle stalling: 1. Unstable idle speed and stalling are relatively common issues in older cars, with symptoms including fluctuating RPMs and idle speed dropping low enough to cause stalling. The root of the problem can be traced by examining aspects related to idle control. 2. There are numerous reasons that can lead to unstable engine idle speed, with throttle carbon buildup being just one of the most common and simplest causes. Other factors like ignition timing, air intake system leaks, fuel injection pressure, PVC valve failures, etc., can also cause unstable idle speed and stalling. These issues can be accurately diagnosed by reading the engine data stream through an OBD diagnostic system to pinpoint the exact cause.
I've been driving for twenty years and seen too many of these issues. Idle stalling is usually caused by problems in the fuel system, electrical system, or air intake. Think about it - an engine needs three things to run: fuel, spark, and air. In the fuel system, it could be clogged fuel injectors, like a showerhead getting blocked and water not flowing smoothly. For the electrical system, it might be worn spark plugs with weak ignition or faulty ignition coils. The most common air intake issue is carbon buildup on the throttle body, like having something stuck in your throat when breathing. Older cars especially need to watch the PCV valve - that little rubber hose breaking can cause trouble too. Don't panic when this happens - first check if the tachometer jumps erratically before stalling, as this can help mechanics quickly diagnose the problem.
