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AC DELCO 213-3521 [KNOCK (DETONATION) SENSOR]

This AC DELCO knock or detonation sensor is a new part. It is the same piece that you would receive if you purchased it from your local GM dealer.

A knock sensor is like a very small electric microphone that is placed on the engine. It listens for pre ignition knocks and then sends a signal to the ECM. The ECM then will make adjustments to the engines timing. If the knock sensor fails, it possibly can cause serious engine damage as continuous pre ignition can cause a fracture in the pistons!

This knock sensor features the following Specifications

  • Brand New AC Delco part
  • Replaces dealer part number: 12589867, 213-3521
  • Built to strict quality control standards
  • Direct replacement
  • 100% factory tested
  • Mounts in either the engine block, cylinder head, or intake manifold
  • (1) Wire Style

Our electrical and electronic parts are subject to strict quality control testing. Please ensure proper diagnosis of this item before purchasing as the item cannot be returned once installed or plugged in.

Item Condition: New

Lifetime Warranty

This item is backed by a Limited Lifetime Warranty. In the event this item should fail due to manufacturing defects during intended use, we will exchange the part free of charge (excludes shipping charges) for the original purchaser.

  1. step : Removing the Air Intake Hose (0:48)
    • Remove the 8mm bolt holding the engine cover
    • Loosen the air intake hose clamps with a flat blade screwdriver
    • Unclip the intake hose from the radiator hose
    • Pull the intake hose up and out
  2. step : Disconnecting the Intake Manifold (1:30)
    • Remove the 8mm bolts
    • Disconnect the harnesses by pulling up on the tab
    • Pry the vacuum hose free
    • Remove the 10mm nuts from the throttle body
    • Lift up the bracket and pull it aside
    • Remove the 8mm bolt and the pull the bracket aside
    • Disconnect the two hose plants and harnesses
    • Remove the 10mm nut and pull the set of harnesses aside
  3. step : Disconnecting the Fuel Line (3:47)
    • Disconnect the eight harnesses to the fuel injector by pulling up on the tab
    • Loosen the fuel line cap
    • Covering the fuel line with a rag, push the tab on the fuel bleeder with a flat head screwdriver
    • Replace the cap
    • Remove the clip
    • Push the fuel line separator tool all the way in and pull the fuel line free
    • Clamp the vacuum hose clamp with pliers and pull it free
  4. step : Removing the Intake Manifold (5:26)
    • Remove the series of 10mm bolts
    • Maneuver the intake manifold past harnesses and wires and move it as far as possible
    • Feed the EGR out through the harnesses
    • Lift the intake manifold up and out
  5. step : Removing the Engine Knock Sensors (7:24)
    • Pry up the knock sensor harness caps
    • Push in the sides of the harness with bent needle nose pliers and pull up
    • Remove the knock sensors with a 22mm socket
  6. step : Installing the Engine Knock Sensors (8:03)
    • Feed the knock sensor into place and tighten it with a 22mm socket
    • Push the harness back onto the knock sensor
    • Replace the cap
  7. step : Reinstalling the Intake Manifold (9:06)
    • Set the intake manifold down and pull the vacuum hose out through the other side
    • Disconnect the EGR by pulling out on the clip with a flat blade screw driver
    • Feed the hose through the side of the intake manifold
    • Maneuver the intake manifold down and into place
  8. step : Reconnecting the Fuel Line (10:14)
    • Reconnect the fuel lines
    • Replace the clips to lock the lines
    • Slide the hose clamp back into place using pliers
    • Line up the throttle body and reconnect it by pushing it up on the studs
    • Push the EGR valve back into place, replace the bolt, and reconnect the hose
    • Reconnect the vacuum hose into the throttle body
  9. step : Reconnecting the Intake Manifold (12:24)
    • Replace the 10mm bolts
    • Replace the bracket near the back
    • Torque the manifold bolts with a torque wrench
    • Start in the middle and work in a counter-clockwise pattern
    • Tighten them on the first pass to 44 inch pounds, then 89 inch pounds
    • Push the harness in and push the clip into place to reconnect the fuel injectors
  10. step : Reinstalling the Air Intake Hose (14:54)
    • Push the intake hose into place
    • Tighten the intake hose clamps with a flat blade screwdriver
    • Double check all the harnesses and hoses
    • Replace the engine cover with an 8mm bolt

Tools needed for replacement:

    Materials, Fluids, and Supplies

  • Rust Penetrant

  • Pliers, Cutters & misc Wrenches

  • Bent Nose Pliers

  • Ratchets & Related

  • Ratchet
  • Socket Extensions
  • Torque Wrench

  • Screwdrivers & Related

  • Flat Blade Screwdriver

  • Sockets - Metric

  • 10mm Socket
  • 22mm Socket
  • 8mm Socket

  • Specialty Tools

  • Fuel Line Disconnect Tool

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Year Make Model Description
2004Buick Rainier Buick Rainier Engine Knock Sensor V8 5.3L (8th Vin Digit P) ACDelco 213-3521
2004-2005Cadillac CTS Cadillac CTS Engine Knock Sensor V8 5.7L (8th Vin Digit S) ACDelco 213-3521
2002-2005Cadillac Escalade Cadillac Escalade Engine Knock Sensor V8 5.3L (8th Vin Digit T) ACDelco 213-3521
2002-2006Cadillac Escalade Cadillac Escalade Engine Knock Sensor V8 6.0L (8th Vin Digit N) ACDelco 213-3521
2003-2006Cadillac Escalade ESV Cadillac Escalade ESV Engine Knock Sensor V8 6.0L (8th Vin Digit N) ACDelco 213-3521
2002-2006Cadillac Escalade EXT Cadillac Escalade EXT Engine Knock Sensor V8 6.0L (8th Vin Digit N) ACDelco 213-3521
2002-2004Chevy Avalanche 1500 Chevy Avalanche 1500 Engine Knock Sensor V8 5.3L (8th Vin Digit T) ACDelco 213-3521
2005-2006Chevy Avalanche 1500 Chevy Avalanche 1500 Engine Knock Sensor V8 5.3L (8th Vin Digit Z) ACDelco 213-3521
1998-2002Chevy Camaro Chevy Camaro Engine Knock Sensor V8 5.7L (8th Vin Digit G) ACDelco 213-3521
1998-2004Chevy Corvette Chevy Corvette Engine Knock Sensor V8 5.7L (8th Vin Digit G) ACDelco 213-3521
2001-2004Chevy Corvette Chevy Corvette Engine Knock Sensor V8 5.7L (8th Vin Digit S) ACDelco 213-3521
2003-2007Chevy Express 1500 Van Chevy Express 1500 Van Engine Knock Sensor V8 5.3L (8th Vin Digit T) ACDelco 213-3521
2007Chevy Express 1500 Van Chevy Express 1500 Van Engine Knock Sensor V8 5.3L (8th Vin Digit Z) ACDelco 213-3521
2003-2007Chevy Express 2500 Van Chevy Express 2500 Van Engine Knock Sensor V8 4.8L (8th Vin Digit V) ACDelco 213-3521
2003-2007Chevy Express 2500 Van Chevy Express 2500 Van Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2003-2005Chevy Express 2500 Van Chevy Express 2500 Van Engine Knock Sensor V8 5.3L (8th Vin Digit T) ACDelco 213-3521
2003-2007Chevy Express 3500 Van Chevy Express 3500 Van Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2005-2007Chevy Express 3500 Van Chevy Express 3500 Van Engine Knock Sensor V8 4.8L (8th Vin Digit V) ACDelco 213-3521
2003-2004Chevy SSR Chevy SSR Engine Knock Sensor V8 5.3L (8th Vin Digit P) ACDelco 213-3521
1999-2007Chevy Silverado 1500 Chevy Silverado 1500 Engine Knock Sensor V8 4.8L (8th Vin Digit V) ACDelco 213-3521
1999-2007Chevy Silverado 1500 Chevy Silverado 1500 Engine Knock Sensor V8 5.3L (8th Vin Digit T) ACDelco 213-3521
2002-2007Chevy Silverado 1500 Chevy Silverado 1500 Engine Knock Sensor V8 5.3L (8th Vin Digit Z) ACDelco 213-3521
2003-2006Chevy Silverado 1500 Chevy Silverado 1500 Engine Knock Sensor V8 6.0L (8th Vin Digit N) ACDelco 213-3521
2005Chevy Silverado 1500 Chevy Silverado 1500 Engine Knock Sensor V8 5.3L (8th Vin Digit B) ACDelco 213-3521
2007Chevy Silverado 1500 Classic Chevy Silverado 1500 Classic Engine Knock Sensor V8 4.8L (8th Vin Digit V) ACDelco 213-3521
2007Chevy Silverado 1500 Classic Chevy Silverado 1500 Classic Engine Knock Sensor V8 6.0L (8th Vin Digit N) ACDelco 213-3521
2007Chevy Silverado 1500 Classic Chevy Silverado 1500 Classic Engine Knock Sensor V8 5.3L (8th Vin Digit Z) ACDelco 213-3521
2007Chevy Silverado 1500 Classic Chevy Silverado 1500 Classic Engine Knock Sensor V8 5.3L ACDelco 213-3521
2001-2003Chevy Silverado 1500 HD Chevy Silverado 1500 HD Engine Knock Sensor V8 6.0L ACDelco 213-3521
2005-2006Chevy Silverado 1500 HD Chevy Silverado 1500 HD Engine Knock Sensor V8 6.0L ACDelco 213-3521
2007Chevy Silverado 1500 HD Classic Chevy Silverado 1500 HD Classic Engine Knock Sensor V8 6.0L ACDelco 213-3521
1999-2004Chevy Silverado 2500 Chevy Silverado 2500 Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
1999-2000Chevy Silverado 2500 Chevy Silverado 2500 Engine Knock Sensor V8 5.3L (8th Vin Digit T) ACDelco 213-3521
2001-2004Chevy Silverado 2500 HD Chevy Silverado 2500 HD Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2001-2006Chevy Silverado 2500 HD Chevy Silverado 2500 HD Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2007Chevy Silverado 2500 HD Classic Chevy Silverado 2500 HD Classic Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2001-2006Chevy Silverado 3500 Chevy Silverado 3500 Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2007Chevy Silverado 3500 Classic Chevy Silverado 3500 Classic Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2000-2005Chevy Suburban 1500 Chevy Suburban 1500 Engine Knock Sensor V8 5.3L (8th Vin Digit T) ACDelco 213-3521
2002-2006Chevy Suburban 1500 Chevy Suburban 1500 Engine Knock Sensor V8 5.3L (8th Vin Digit Z) ACDelco 213-3521
2006Chevy Suburban 1500 Chevy Suburban 1500 Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2000-2006Chevy Suburban 2500 Chevy Suburban 2500 Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2000-2006Chevy Tahoe Chevy Tahoe Engine Knock Sensor V8 4.8L (8th Vin Digit V) ACDelco 213-3521
2000-2006Chevy Tahoe Chevy Tahoe Engine Knock Sensor V8 5.3L (8th Vin Digit T) ACDelco 213-3521
2002-2006Chevy Tahoe Chevy Tahoe Engine Knock Sensor V8 5.3L (8th Vin Digit Z) ACDelco 213-3521
2003-2004Chevy Trailblazer EXT Chevy Trailblazer EXT Engine Knock Sensor V8 5.3L (8th Vin Digit P) ACDelco 213-3521
2003-2004GMC Envoy XL GMC Envoy XL Engine Knock Sensor V8 5.3L (8th Vin Digit P) ACDelco 213-3521
2003-2007GMC Savana 1500 Van GMC Savana 1500 Van Engine Knock Sensor V8 5.3L (8th Vin Digit T) ACDelco 213-3521
2007GMC Savana 1500 Van GMC Savana 1500 Van Engine Knock Sensor V8 5.3L (8th Vin Digit Z) ACDelco 213-3521
2003-2007GMC Savana 2500 Van GMC Savana 2500 Van Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2003-2007GMC Savana 2500 Van GMC Savana 2500 Van Engine Knock Sensor V8 4.8L (8th Vin Digit V) ACDelco 213-3521
2003-2005GMC Savana 2500 Van GMC Savana 2500 Van Engine Knock Sensor V8 5.3L (8th Vin Digit T) ACDelco 213-3521
2003-2007GMC Savana 3500 Van GMC Savana 3500 Van Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2004-2007GMC Savana 3500 Van GMC Savana 3500 Van Engine Knock Sensor V8 4.8L (8th Vin Digit V) ACDelco 213-3521
1999-2006GMC Sierra 1500 GMC Sierra 1500 Engine Knock Sensor V8 4.8L (8th Vin Digit V) ACDelco 213-3521
1999-2006GMC Sierra 1500 GMC Sierra 1500 Engine Knock Sensor V8 5.3L (8th Vin Digit T) ACDelco 213-3521
2001-2006GMC Sierra 1500 GMC Sierra 1500 Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2002-2006GMC Sierra 1500 GMC Sierra 1500 Engine Knock Sensor V8 5.3L (8th Vin Digit Z) ACDelco 213-3521
2005GMC Sierra 1500 GMC Sierra 1500 Engine Knock Sensor V8 5.3L (8th Vin Digit B) ACDelco 213-3521
2006GMC Sierra 1500 GMC Sierra 1500 Engine Knock Sensor V8 6.0L (8th Vin Digit N) ACDelco 213-3521
2007GMC Sierra 1500 Classic GMC Sierra 1500 Classic Engine Knock Sensor V8 4.8L (8th Vin Digit V) ACDelco 213-3521
2007GMC Sierra 1500 Classic GMC Sierra 1500 Classic Engine Knock Sensor V8 5.3L (8th Vin Digit Z) ACDelco 213-3521
2007GMC Sierra 1500 Classic GMC Sierra 1500 Classic Engine Knock Sensor V8 5.3L ACDelco 213-3521
2007GMC Sierra 1500 Classic GMC Sierra 1500 Classic Engine Knock Sensor V8 6.0L (8th Vin Digit N) ACDelco 213-3521
2007GMC Sierra 1500 Classic GMC Sierra 1500 Classic Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2001-2003GMC Sierra 1500 HD GMC Sierra 1500 HD Engine Knock Sensor V8 6.0L ACDelco 213-3521
2005-2006GMC Sierra 1500 HD GMC Sierra 1500 HD Engine Knock Sensor V8 6.0L ACDelco 213-3521
2007GMC Sierra 1500 HD Classic GMC Sierra 1500 HD Classic Engine Knock Sensor V8 6.0L ACDelco 213-3521
1999-2004GMC Sierra 2500 GMC Sierra 2500 Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
1999-2000GMC Sierra 2500 GMC Sierra 2500 Engine Knock Sensor V8 5.3L (8th Vin Digit T) ACDelco 213-3521
2001-2004GMC Sierra 2500 GMC Sierra 2500 Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2001-2004GMC Sierra 2500 HD GMC Sierra 2500 HD Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2001-2006GMC Sierra 2500 HD GMC Sierra 2500 HD Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2007GMC Sierra 2500 HD Classic GMC Sierra 2500 HD Classic Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2001-2006GMC Sierra 3500 GMC Sierra 3500 Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2007GMC Sierra 3500 Classic GMC Sierra 3500 Classic Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2000-2006GMC Yukon GMC Yukon Engine Knock Sensor V8 4.8L (8th Vin Digit V) ACDelco 213-3521
2000-2006GMC Yukon GMC Yukon Engine Knock Sensor V8 5.3L (8th Vin Digit T) ACDelco 213-3521
2002-2006GMC Yukon GMC Yukon Engine Knock Sensor V8 5.3L (8th Vin Digit Z) ACDelco 213-3521
2004-2006GMC Yukon GMC Yukon Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2000-2005GMC Yukon XL 1500 GMC Yukon XL 1500 Engine Knock Sensor V8 5.3L (8th Vin Digit T) ACDelco 213-3521
2002-2006GMC Yukon XL 1500 GMC Yukon XL 1500 Engine Knock Sensor V8 5.3L (8th Vin Digit Z) ACDelco 213-3521
2000-2005GMC Yukon XL 2500 GMC Yukon XL 2500 Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2003-2007Hummer H2 Hummer H2 Engine Knock Sensor V8 6.0L (8th Vin Digit U) ACDelco 213-3521
2003-2004Isuzu Ascender Isuzu Ascender Engine Knock Sensor V8 5.3L (8th Vin Digit P) ACDelco 213-3521
1998-2002Pontiac Firebird Pontiac Firebird Engine Knock Sensor V8 5.7L (8th Vin Digit G) ACDelco 213-3521
2004Pontiac GTO Pontiac GTO Engine Knock Sensor V8 5.7L (8th Vin Digit G) ACDelco 213-3521
Part #: 1AACD00047


Order must be placed by 4pm ET

Get it in: 2 - 4 Business Days

Want it sooner? Choose Next Day Air at Checkout

AC DELCO
Brand #: 213-3521

How-to Video:

(15:52 min)