Why is it difficult to start a car when it's hot?
1 Answers
Difficulty in starting a hot sedan is often caused by excessive carbon deposits in areas such as the throttle body, idle speed motor, intake manifold, and combustion chamber. Below is a detailed explanation of the reasons: Carbon Deposits: Carbon deposits have a strong adsorption effect on gasoline. If there are excessive carbon deposits on the intake valve, throttle body, or piston, they can absorb some fuel, leading to an overly lean air-fuel mixture, which affects starting. Damaged or Leaking Carbon Canister Solenoid Valve: The carbon canister solenoid valve controls the flow of fuel vapor from the carbon canister. After the engine is turned off, gasoline vapor mixes with fresh air in the canister and is stored in the activated carbon canister. When the engine starts, the solenoid valve between the activated carbon canister and the intake manifold opens, allowing the gasoline vapor in the canister to be drawn into the cylinders by the vacuum in the intake manifold, where it is burned. Ignition Coil: When the ignition coil heats up, the resistance of the wires increases, weakening the primary current. As a result, the voltage in the secondary coil decreases, leading to weaker sparks. This reduction in ignition energy may cause difficulty in starting the engine.
