What are the reasons for difficulty in ignition after warming up the car?
2 Answers
The reasons for difficulty in ignition after warming up the car are as follows: 1. Excessive carbon deposits on the spark plug electrodes or excessive gap between the spark plug electrodes, resulting in poor ignition and difficulty in starting. 2. Excessive dust in the intake system (mainly reflected in the air filter and throttle body), causing poor air intake, or excessive carbon deposits on the intake manifold affecting the mixture of gasoline and air, leading to difficulty in ignition. 3. Insufficient fuel pressure causing ignition difficulties: (1) A dirty fuel filter causing blockage in the fuel supply line. (2) Damaged fuel pump, unable to provide sufficient fuel supply pressure. 4. Damaged fuel pressure regulator, unable to properly regulate the pressure of the fuel pumped out by the fuel pump.
I found that the car has difficulty starting after warming up, and there are several technical reasons behind this. The most common issues are aging spark plugs or carbon buildup. After warming up, the increased temperature can cause changes in the spark plug gap, reducing ignition efficiency. The fuel system is also critical—insufficient fuel pump pressure or clogged fuel injectors become more apparent in hot conditions, leading to improper fuel delivery. Additionally, damaged ignition coils show obvious symptoms at high temperatures, as the insulation performance of aging coils deteriorates, weakening or even eliminating the spark. Faulty sensors, such as the coolant temperature sensor, can also trick the computer system, causing misjudgment of temperature and delayed starts. Poor electrical connections may loosen further due to thermal expansion, increasing resistance and current loss. These problems can accumulate over time, so regular checks of spark plugs, carbon cleaning, and fuel pressure tests can help prevent them. If the issue persists, I always recommend visiting a professional shop for diagnosis to avoid being stranded on the road.