How to Check if a Car Has Carbon Deposits?

[JosieAnn]

Methods to check if a car has carbon deposits are: 1. Disassemble the engine and inspect for carbon deposits; 2. Remove the spark plugs or fuel injectors and use an endoscope to observe the extent of carbon deposits on the valves; 3. Ensure the car is stationary for more than 5 minutes, then open the engine oil filler port and observe the engine crankshaft through it, as carbon deposits can adhere to the crankshaft; 4. Remove the intake hose of the throttle body for a clear view. Carbon deposits are a coking-like substance formed from unsaturated olefins and gums in fuel under high temperatures during engine operation. If carbon deposits have already caused issues such as idle shaking, difficulty starting, high idle speed, or excessive exhaust emissions, cleaning is necessary. Cleaning can be done using some no-disassembly cleaning agents.