* Idle Air Control Valve (IACV): The IACV is responsible for controlling the amount of air that bypasses the throttle body at idle. If the IACV is faulty or dirty, it can cause the engine to hunt.
* Throttle Position Sensor (TPS): The TPS is responsible for sending a signal to the engine's computer (PCM) about the position of the throttle. If the TPS is faulty or misadjusted, it can cause the engine to hunt.
* Vacuum Leak: A vacuum leak can cause the engine to run lean, which can lead to hunting. Check for any loose or cracked vacuum hoses.
* Fuel Pressure: Low fuel pressure can also cause the engine to hunt. Check the fuel pressure at the fuel rail to ensure that it is within specifications.
* PCM Issue: In some cases, a hunting engine can be caused by a problem with the PCM. If you have tried all of the above steps and the engine is still hunting, you may need to have the PCM checked by a qualified technician.
