REPLACEMENT KNOCK SENSOR : A knock sensor is located on the intake manifold, cylinder, or engine block. The purpose of the knock sensor is to sense unusual pulsations caused by the engine knock or detonation. Symptoms of a bad knock sensor are check engine light CEL on, loud sounds, bad fuel mileage, poor acceleration and poor engine performance. When you replace the knock sensor please be careful the grime fall into the cylinders when you pull the intake manifold off. COMPATIBLE WITH for , VEHICLES : 2003 2004 2005 2006 2007 Accord; 2002 2003 2004 2005 2006 2007 2008 2009 ; 2002 2003 2004 2005 ;2003 2004 2005 2006 2007 2008 2009 2010 2011 Element; 2007 2008 2009 2010 2011 2012 ; 2002 2003 2004 2005 2006 RSX; 2004 2005 2006 2007 2008 TSX knock sensor. Please check the description to confirm the compatibility before purchase. Thank you! REPLACES PART NUMBER# : 30530-PPL-A01, 30530PPLA01, 158-0917, 1580917 knock sensor. colour: black + silver Material: Metal+Plastic Package Contents: 4 x Knock Sensor Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.