P0326

[stonie083]

I drive a 2017 Silverado 1500. I have had a code pop up, p0326 knock sensor circuit excessive spark r*tard, specifically Bank 1. I have not noticed any loss of power or heard or noticed any other signs of knock. The problem is the light goes on and off somewhat randomly. Might be on for a couple days then don’t see it for two weeks, then it’s on for a week and a half, off again, etc. so no shop is willing to look at it. Since I have not noticed any loss of power and how it is acting up I am wondering if it is simply bad sensor/wiring. At this point I want to find it and fix it myself but I have been unable to find any diagram of where the sensor is. Looking for some help.

Edited November 24, 2021 by stonie083
Blocked word

[Jsdirt]

Couldn't tell you where they're located on a '17, but on prior years they were under the intake manifold. I'd assume they're probably in the same location, since GM rehashes designs for years, even when riddled with failures (AFM lifters are a prime example of that).

 

So if you don't hear any spark knock or feel loss of torque, it's either a bad sensor, connector pin, or a wiring issue. You could fire up a scan tool and watch live data on timing as you wiggle sections of the harness all the way to the PCM. Any abrupt changes would indicate some wiring issues in the area you were touching or wiggling. If you don't have a scan tool, you could use a timing light just to note any changes in timing, but you'll have to number a section of the balancer from TDC and before, since timing marks are no longer used these days.

 

If it becomes too big of a PITA, and you're in western NY or PA, I know of a couple top notch electrical troubleshooters there I could steer you towards. Even if your several hours out, it would be worth the trip.

[Ianf]

I believe the sensors since 2008 are on the side of the block just above and in front of the oil filter. easy to change out and check the wiring. Just did my driver side one while under doing my oil change in about a minute and a half. One connector and one 13mm bolt.

 

 

[Jsdirt]

 Yep, forgot the 900 series completely changed the location. The VLOM is under the intake, at least for '07-'13. Thanks for the memory jog, Ian. 

Edited November 26, 2021 by Jsdirt