What Causes the Engine RPM to Fluctuate While Driving?

[LaReagan]

The reasons for fluctuating engine RPM while driving: 1. Charging system malfunction, which could be due to alternator failure, battery voltage sensor malfunction, or loose battery terminals; 2. Throttle body issues, possibly caused by throttle position sensor failure or throttle control motor malfunction; 3. Faulty PCV valve or charcoal canister solenoid valve; 4. Engine carbon buildup. An engine is a machine that converts other forms of energy into mechanical energy, including internal combustion engines, external combustion engines, jet engines, electric motors, etc. For example, internal combustion engines typically convert chemical energy into mechanical energy. The term engine can refer to either the power generation device or the entire machine including the power unit.