I have purchased these recommended knock sensors and wire harnesses for my 2005 Fleetwood Southwind 37L (Workhorse W22 w/ 8.1L Vortec)...I can reset the OBD2 codes and the check engine light stays off until I start the engine up again...then the check engine light comes on after a few minutes...same knock sensor codes.... clear the codes and the check engine light stays out for as long as the engine is running (10 minutes or 4+ hours)...shut engine off to re-fuel...re-start and the light will come on in just a few minutes. Any suggestions on what else I could check? ( Chris , 11/19/2024 )
This has become somewhat of an known issue with the 8.1L as of the last couple years. We have not been able to isolate the issues to any one thing, sometimes it's the wiring to the sensor from the ECM, sometimes it is the ECM itself and other times there simply is no issues found. In the last case scenario, there is an option to "turn off" the codes in the ECM so that it no longer reports this issue. We only recommend doing this if all other avenues have been exhausted as it will eliminate the check engine light from ever coming on due to a knock sensor issue.
Is this the OEM GM knock sensor for 12591312 or is this an aftermarket OEM alike one?

 ( Andy, 01/09/2024 )
The OEM part has been discontinued, we have an aftermarket replacement : 

12591312AF - Knock Sensor Asm 

PO135 code on reader. 2005 Workhorse 8.1 Is the KS 112 a replacement for this vin # ? Who is the manufacture and assembly origin ? Also referring to diagram items 5&6, is this sensor the same for bank ! or Bank 2 ( Frank Freeman, 05/18/2023 )
Yes, this is the replacement part # for your 8.1L V8 knock sensor. It is the same sensor on bank 1 and bank 2. The manufacturer is SMP and they are assembled in Mexico.
Is this the part i need for this vehicle thank you ( david steaven keith, 10/26/2022 )
Yes, that is the correct knock sensor for that VIN . 
Will these work on my 08 Kodiak C5500 with the 8.1.
Thanks ( 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 #.