Why does the car stall without stepping on the accelerator?
2 Answers
Reasons why the car stalls without stepping on the accelerator: 1. Generally, it is due to poor fuel quality that fails to meet the required heat value. 2. Low ignition energy, excessive spark plug gap, aging ignition coil, poor combustion, malfunctioning coolant temperature sensor, or poor EGR valve operation. 3. It is particularly important to note that long-term use of low-quality fuel can cause premature aging of internal spark plugs. The increased spark plug gap can lead to fuel injector damage, resulting in engine misfire and stalling at idle. Additional information: A typical fault where the car requires stepping on the accelerator to start occurs when the battery voltage and starter operation are normal, but the engine fails to start. It either requires slightly pressing the accelerator to start or has difficulty with cold starts. Possible causes include faults in the throttle body, idle switch, coolant temperature sensor, intake air temperature sensor, etc. Additionally, the use of poor-quality fuel in the car leads to suboptimal combustion effects in the engine.
I've encountered a similar issue recently – the car stalls as soon as I release the throttle, which is really annoying. Last time when I drove my uncle's Corolla with 100,000 kilometers on it, it had the same problem. The diagnosis showed that the throttle valve was completely clogged with carbon deposits, but it worked perfectly again after cleaning. Engine carbon buildup is such a common troublemaker, just like how a range hood gets clogged with grease if not cleaned for a long time. The fuel system can also cause trouble frequently – issues like insufficient fuel pump pressure or clogged fuel injectors can lead to poor fuel supply. In my opinion, the simplest first step is to check the idle speed; normally it should be around 750 RPM, and if it's below 600 RPM, it's likely an issue with the idle air control valve or throttle position sensor. If that doesn't solve it, check the spark plugs – aging ignition coils could also cause stalling.
