P1299 P1299 OBD Code Definition: P1299 Vacuum Leak Found (IAC Fully Seated) P1299 OBD Code Description: OBD Code P1299 Vacuum Leak Found (IAC Fully Seated) OBD Code P1299 Cylinder Head Temperature Sensor Detected Engine Overheating Condition OBD Code P1299 Cylinder head overtemperature protection active OBD Code P1299 Fuel metering solenoid – circuit malfunction