ROADFAR Detonation Knock Sensor with Harness 2206030P00 Fit for Infiniti G20 I30 J30 Q45 QX4-for Mercury Villager-for Nissan 200SX 240SX 300ZX Altima D21 Maxima NX Pickup Quest Sentra Xterra 2Pins

Knock sensor is designed to detect when the combustion in car is not being properly controlled.A knock sensor uses an internal element that is extremely sensitive to vibration and will detect when the pressure wave from the combustion hits the cylinder wall before it is supposed to.When the sensor detects incorrect noise from internals of the motor it will retard the timing in order to protect the engine.The sensor has been designed to act as if mechanic was listening to the engine and keeping an eye on the things for the driver. Notice : Please find the amazon fitment on the top of the page,enter your vehicle information to check if the item fit your vehicle Fitment: 1991-1996 1999-2002 for Infiniti G20 2.0L 1996-2001 for Infiniti I30 3.0L 1993-1997 for Infiniti J30 3.0L 1997-2001 for Infiniti Q45 4.1L 1990-1996 for Infiniti Q45 4.5L 1997-2000 for Infiniti QX4 3.3L 1993-1998 for Mercury Villager 3.0L 1995-1998 for Nissan 200SX 2.0L 1987-1988 for Nissan 200SX 3.0L 1989-1998 for Nissan 240SX 2.4L 1987-1996 for Nissan 300ZX 3.0L 1993-2001 for Nissan Altima 2.4L 1986-1994 for Nissan D21 2.4L 1986-1994 for Nissan D21 3.0L 1992-1993 1995-1999 for Nissan Maxima 3.0L 1991-1993 for Nissan NX 2.0L 1987-1988 for Nissan Pathfinder 2.4L 1987-1995 for Nissan Pathfinder 3.0L 1996-2000 for Nissan Pathfinder 3.3L 1995-2004 for Nissan Pickup 2.4L 1995-1996 for Nissan Pickup 3.0L 1993-1998 for Nissan Quest 3.0L 1991-1994 1998-2001 for Nissan Sentra 2.0L 2000-2004 for Nissan Xterra 2.4L one knock sensor and harness