12591312 - 8.1L Knock Sensor Asm

12591312 - 8.1L Knock Sensor Asm


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Part# 12591312



  • Brand New Workhorse Knock Sensor Assembly for all 8.1L Engines in Workhorse Chassis.


  • All Workhorse Chassis Equipt with an 8.1L Engine


  • This item must be installed to a torque value of 15 lbs ft with dry threads or it will not function properly.
Will these work on my 08 Kodiak C5500 with the 8.1.
( JR Mascarenas , 07/14/2020 )
Unfortunately we are unable to lookup part #'s for your Chevrolet C5500, however, I do believe all of the 8.1L's use these same knock sensors. You would be able to confirm by contact a GM dealer and having them verify the part #. ( Support )
Have a code PO332 and PO327 on a 2005 Admiral Workhorse with an 8.1L. Do you have a diagram that shows where these sensors are? ( Kyle Watson, 05/14/2020 )
( Support )
2005 24W Workhorse 8.1 L Motorhome
Reading codes 332 and 327 knock sensor 1 and 2
Are they the same model # 12591312 sensors and pigtails ?

Also reading code 463 Fuel level sensor
( James Thomas, 05/03/2020 )
James, I have sent the required diagnostic information to your email. Please read through this information to find out what parts would be required to resolve the codes you have present. ( Support )
I have a 03 motorhome on a w22 workhorse chassis with a 8.1 engine...what part number do I ned to order for the nati knock sensors and pig tail.. ( lc, 04/18/2020 )
Knock sensor for your 8.1L is part # 12591312 and pigtail is part # 15306376. ( Support )
Are these the correct sensors for my vin ? Does a certified mechanic required to install? ( Kenny Bracken, 11/01/2019 )
Hello, your vin# did not come through. A certified mechanic is not required to install, ( Support )
I just got CODE PO332 on my 2007 Workhorse W22 (Engine Light) - Would this be the issue? Also are there more than one (1)? Should I also replace the pigtail wiring to both? It appears this is the correct part for my chassis. ( Wilfred Bush, 06/26/2019 )
This is the correct part but we are emailing you the diagnostic trouble shooting steps for that code to aid in diagnosing the issue. ( Support )
Do you have the plug/wire for this sensor? ( Roy Chapman, 12/03/2017 )


The pigtail for this sensor is part# 15306376

( Support )
I have a 2003 Winnebago Brave, Workhorse chassis, and 8.1 Vortec. Is this knock sensor OEM? It appears it may be based on number. ( Jim Muir, 06/05/2016 )


Yes this is the OEM knock sensor for your 8.1L.

( Support )

Hi Do you need to change both sensors if only one is giving the error reading Cheers Peter

( Peter, 02/04/2016 )


It would not be necessary but it wouldn't be a bad idea to do so. 

( Support )

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WARNING: Products may contain one or more chemicals known in the State of California to cause cancer and/or birth defects or other reproductive harm. For more information, visit www.P65Warnings.ca.gov

VIN Verification Service Item

This product allows for a VIN verification service.

  • This is a service that we provide free of charge when a part is purchased.
  • When you provide your VIN below we will personally verify your part selection by your VIN before shipment of your order.
  • This helps ensure that this is the correct part for your vehicle.
  • This is not an automatic VIN check, it is done by a parts specialist once order is placed.
  • We can only VIN verify vehicles back to model year 1996, if older we can help but can't guarantee fitment.
  • If you would like to have your part selection verified before purchase please call or email us.

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  • $101.98
  • $75.54

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