GM Truck Club
THE PREMIER CHEVY TRUCK & SUV FORUM
Founded in 2004 ~ We're the #1 Chevy Truck & SUV Forum.
Silverado & Sierra | Tahoe & Yukon | Suburban & Yukon XL | SUV & CROSSOVER
Results 1 to 6 of 6

Thread: Knock Sensor

  1. #1

    Default Knock Sensor

    My 2002 Suburban with the 5.3 L,flex fuel engine (Z) pulled a P0332 DTC today. The manual says that is the rear knock sensor. To get to the knock sensor, you have to take all of the fuel injection hardware as well as the intake manifold off. Before I do all that work, I want to ask if others have had this problem before and was it typically the sensor? Or was is a bad connection on the top of the sensor? Should I go for exact GM replacement?

    Finally, can I go a few days before I replace the knock sensor? With a malfunctioning knock sensor, will the engine computer permanently place the engine on retarded timing?

    Thanks.

  2. #2

    Default

    I believe dsfloyd just did his.
    :cool:

    2005 Chevy Silverado Z71 Crew Cab
    6" Skyjacker lift w/Edlebrock dual front remote resoviour shocks, single rear remote. Rancho skid-plate.
    17" x 9" M/T Classic Lock Wheels, 35" BFG A/T or M/T tires
    4.10 PercisionGears w/factory locker, T/A Performance rear-end cover
    Banks CAI intake, ported throttlebody, JBA coated headers, over-sized Magnaflow cats, Magnaflow cat back exhaust, Diablo tuned
    B&M aluminum deep transmission pan
    Warn brush guard w/Warn 9.5 XP winch, PIAA bulbs, Line-X bedliner, AWS Black tool chest, Extang tonneau cover
    Weather Tech floor mats
    Cover-Craft seat covers
    Dash mat cover
    Formula One window tint
    One black Lab in rear seat.
    :glasses:

  3. #3

    Default

    Many thanks to dsfloyd and silveradotrailblazer. When I got into the job, I found out that the rear sensor was very rusty while the front sensor looked like a new one. It looks like water had gotten into the rear sensor well and did the deed over the years. The connector even looked bad for the rear sensor, so I got a new wiring harness as well. The local GM dealer had a number of wiring harnesses in stock which leads me to think that they replace them often. My recommendation is to order two knock sensors, a manifold gasket set and the knock sensor wiring harness (P/N 12601822). Then be sure to use a little RTV when you insall the wiring harness plug.

    One final thing. I couldn't find any information on how to release the connector on the knock sensor. It took a while to finally figure it out. Take a pair of pliers and squeeze the two flat surfaces down low along the sides of the connector and it will pop right off.

  4. #4

    Default

    Knock sensor replacement on LS1 engines are a pain. They're located UNDER the intake manifold. There is two sensors in two identical indentations on the top of the block. Moisture gets under the intake manifold and settles in those indentations and rusts the knock sensors. By bad design on GM's part.

    To replace the senors remove your intake manifold, and pop off the two rubber grommets that are on the top of the block, there should be one wire coming out of each.

    Click image for larger version. 

Name:	TifToGif.jpg 
Views:	475 
Size:	19.2 KB 
ID:	29604
    There's going to be a plastic connection that connects to the top of the knock sensor. I would highly recommend purchasing two new pigtails. 90% of the time they break during removal. Easy to replace, cut the wire crimp the two wires together from the pig tail to the stock wire, heat shrink it water tight.

    To remove the knock sensor just take your ratchet and socket and unscrew from the block.
    Click image for larger version. 

Name:	TifToGif1.jpg 
Views:	445 
Size:	18.5 KB 
ID:	29605
    Then when doing the installation, be sure to use rtv silicone to seal the grommet water tight and air tight.
    Click image for larger version. 

Name:	TifToGif2.jpg 
Views:	384 
Size:	20.4 KB 
ID:	29606
    www.youtube.com/ippielb
    2002 Chevrolet Silverado 1500 z71 1985 Chevrolet Silverado k10 2006 Chevrolet Silverado 2500hd 6.6l LLY Duramax
    6.5" BDS Suspension Lift Edelbrock Carb & Polished Intake Manifold & Valve Covers NAPC Race Transmission & NAPC Built Transfer Case
    EFI Live Comp Cam and Valvetrain Snow Performance Methanol Injection
    35" Toyo Open Country Mud Terrain on 18" Ion Alloy 179's Headman Long Tube Headers and True Dual Exhaust FASS 150gph Titanium Series Pump
    AirAid Cold Air Intake with K&N Dry Filter & AirAid PowerAid Throttle Body Spacer 2" Suspension Lift 33x12.50r15 Tires EFI Live & AFE Stage 2 Intake
    Pacesetter Long Tube Headers with Cats Gone True Dual Exhaust FlowPro 3.73 Gears Yukon Grizzly Locker with Mag-Hytec Cover & Traction Bars
    NGK Iridium Tips & MSD Ignition Plug Wires Baja Spare Tire Holder 33x13.5 Hankook rt03 18" XD Rims
    Innovate LC-1 Wideband o2 Sensor x2 HID's all around LED taillights and 3rd brake light
    BDS Dual Steering Stabilizers Pioneer Double-DIN Touchscreen Navigation with Two 10" Subs under rear seat
    Electric Fan Autometer Pressure, Boost, and Pyro Gauges
    4.56 Gears Airlift Air Bag Suspension

  5. #5

    Default

    Here's some real pictures from an 02' 5.3l that had knock sensors replaced.








    ---------- Post added at 03:25 PM ---------- Previous post was at 03:24 PM ----------





  6. #6

    Default

    I would advise anyone doing this to cover/plug the heads intakes immedatly after removing the manifold so nothing gets dropped in the intake port. I like to use a shop vac to vaccuum the area around the intake maniflod before removing the manifold and then again when the manifold is removed to help keep dirt from getting into the engine.

Similar Threads

  1. knock sensor
    By mikemax in forum General Chevy & GM Tech Questions
    Replies: 3
    Last: 07-26-2011, 02:17 PM
  2. Knock Sensor
    By groceryman in forum General Chevy & GM Tech Questions
    Replies: 5
    Last: 06-15-2011, 03:59 PM
  3. Knock Sensor
    By avionics in forum General Chevy & GM Tech Questions
    Replies: 1
    Last: 06-06-2009, 12:29 PM
  4. Knock sensor
    By 91Chuck in forum GM Powertrain
    Replies: 4
    Last: 05-03-2009, 08:36 PM
  5. Where is knock sensor on 350 TBI?
    By Big6ft6 in forum Chevy Suburban Forum (GMC Yukon XL)
    Replies: 5
    Last: 10-22-2008, 10:19 AM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •