P1159 KIA Possible Causes
- Faulty variable intake motor
- Variable intake motor wiring harness is open or shorted
- Poor electrical connection in variable intake motor circuit
How to Fix P1159 KIA Code?
Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Look for damaged components and check for broken, bent, pushed out, or corroded connector pins.
Possible Symptoms
- Check engine light on (or service engine soon warning light)
P1159 KIA Meaning
The Variable Intake System (VIS) is used to increase low-end torque and boost power at higher RPM. The 3.5ℓ Sigma engine has two intake channels for each cylinder. The primary intake channel is a long, thin tube through which intake air passes. This allows a strong airflow to blow into the cylinder, thus promoting low-end torque. The secondary intake channel is a short, wide tube. This allows a large volume of air to be drawn into the engine, thereby increasing high-end power. At lower RPMs, the engine doesn’t provide enough suction in the cylinders, thus depriving the engine of much-needed oxygen. The narrow tube helps blow air into the cylinder for more oxygen. At higher RPM, the engine has plenty of suction, but the intake channel is too small to provide the oxygen it needs.