A Guangzhou Honda accord 2. 4L with a mileage of about 100 thousand km. User reflection: the engine is difficult to start. Fault diagnosis: 1) check the battery voltage is normal. 2) check the spark plug condition, there is no moisture or carbon deposition. 3) connect the fuel pressure gauge to the fuel line and start the engine to check the oil pressure at 360kPa, within the normal technical range. 4) when starting the engine, it feels that the starter is running incapable. The car has travelled almost 100 thousand km, and suspected that the starter was not properly maintained. 5) remove the starter for testing and find the starter running incapable. 6) decomposing starter, found that the brush wear is serious and has reached the limit position. Replace the starting electrical brush, and use the sandpaper to polish the commutator. After installation, the engine starts normal and troubleshooting.