What are the reasons why the Cavalier's idle speed cannot drop below 1000?
3 Answers
The reasons why the Cavalier's idle speed cannot drop below 1000 are: 1. Throttle sticking or not closing properly; 2. Improper idle adjustment; 3. Additional air valve failure; 4. Idle control valve sticking or control circuit failure; 5. Coolant temperature sensor failure. Taking the 2020 Cavalier as an example, it belongs to the compact car category, with body dimensions of: length 4474mm, width 1730mm, height 1471mm, wheelbase of 2600mm, and a fuel tank capacity of 36l. The 2020 Cavalier is equipped with a 1.0T turbocharged engine, with a maximum horsepower of 125PS, maximum power of 92kW, maximum torque of 180Nm, and is paired with a 6-speed automatic manual transmission.
My Cavalier had the same issue before, the idle speed always stuck above 1000 RPM and wouldn't drop. After several inspections, I found the main culprit was severe carbon buildup in the throttle body. Long-term oil deposits blocked the airflow passage, causing unstable ECU control that maintained high RPM. Another common problem is air leaks in the intake pipe or vacuum hose - like the aged and cracked hose connector discovered in my car. Excess air leakage leads to an overly lean air-fuel mixture, preventing idle speed from dropping. Additionally, the idle air control valve might be stuck or worn out. Faulty sensors like the intake air temperature sensor can also mislead the ECU into misjudging engine temperature, making it think the engine is still cold and requiring higher RPM. If left unfixed, this issue not only wastes fuel (costing dozens extra monthly) but also accelerates internal engine wear and shortens overall vehicle lifespan. I'd suggest starting with a simple throttle body cleaning, but don't take it lightly - visit a professional shop to read trouble codes for proper diagnosis.
Driving a Cavalier with an idle speed stuck at 1000 RPM is quite annoying. After researching, I found several main reasons. A dirty throttle body with excessive carbon buildup is the primary issue—restricted airflow prompts the ECU to compensate by raising idle speed. Next is intake manifold leaks, such as loose or cracked hose connections, causing vacuum leaks that disrupt the air-fuel ratio. A stuck idle control valve or faulty sensors are also common; my car once had a failed temperature sensor that caused ECU miscalibrations. Additionally, worn spark plugs or ignition coil problems reduce combustion efficiency, leading to unstable idle. Persistent high idle not only increases noise but also accelerates engine wear and noticeably raises fuel consumption. DIY solutions include regular cleaning/maintenance or monitoring post-warmup RPM (should drop to ~800); otherwise, address it promptly for safety.
