What are the reasons for difficulty in starting a car when it's hot?
2 Answers
Reasons for difficulty in starting a car when it's hot: 1. Fuel injector leakage: While fuel injection is normal, leakage constitutes additional fuel supply, and the more severe the injector leakage, the richer the air-fuel mixture becomes; 2. Damaged carbon canister solenoid valve: During hot starts, fuel atomization is normally adequate without needing additional fuel vapor. If the carbon canister continues to supply fuel vapor to the intake tract, it will cause an overly rich air-fuel mixture; 3. Fuel quality: After the engine is shut off when hot, the high temperature in the engine compartment causes the fuel to evaporate easily, forming high vapor pressure in the fuel rail. When this pressure exceeds the fuel system's supply pressure, vapor lock occurs, resulting in overly lean fuel vapor from the injectors; 4. Intake air temperature sensor: Similar to the coolant temperature sensor, the intake air temperature sensor adjusts fuel injection. However, while a faulty coolant temperature sensor causes cold start difficulties, a faulty intake air temperature sensor leads to hot start problems.
I previously encountered the frustrating issue of difficulty starting my car when it's hot. It might be due to vapor bubbles forming in the fuel system, as gasoline tends to vaporize under high temperatures, blocking the fuel lines and preventing the engine from getting fuel. It's similar to having air in a water pipe - the fuel pump can't work effectively. I also noticed that when spark plugs have heavy carbon deposits, they fail to ignite properly, especially in older vehicles. Rising temperatures can cause electrical sensors to misread signals, such as the crankshaft position sensor reporting errors, leading to starting failures. It's advisable to regularly inspect the fuel system and ignition components, and avoid prolonged parking under direct sunlight. A simple solution is to let the engine cool down slightly before attempting to restart after parking. If this problem occurs frequently, it's best to take the car to a professional repair shop promptly. Don't underestimate this issue as it affects driving safety.
