What are the problems associated with having this sensor not work properly?

 

HAHA funny you should ask i just repaired mine. I broke it when i pulled the engine. I got a ses light and a lil loss in driveability. Its a easy fix 15 bux from gm and a lil wiring work.

 

I did mine with a longtube install. So it is not hurting anything?

 

A buddy and I just put his motor in lastnight and had this problem. We concluded his brand new Autozone KS was broke or was the wrong one. To check the wiring we had to use his old KS, plug it into the harness and then ground it to the body.. you have to ground it or it will set off the SES light. His old sensor didnt throw a code so we had to replace it with the new one.

The only symptom we had was the SES light. It wasnt pulling any timing.

 

Normally, it causes the PCM to pull a set amount of timing to protect the engine. Performance will suffer.

 

Confirmed!

When the PCM doesn't see the correct voltage on the KS circuit, it sets DTC 43 and defaults to an internal table that will give you full-time knock retard, ranging from a few degrees to 15-degrees. I've confirmed this with my ScanMaster. That will definitely cost you some performance.

 

Fred i'm the guy that Turbo_z is talking about and when the autozone sensor was throwing the code i didn't get any timing pulled out. My pcm has stock KR tables, is there something else that can be wrong?

 

Actually thats not entirely accurate. I remember adding timing now that I think about it. I believe since you were getting some KR at idle I just went ahead and cut it all out... that probably explains why we didnt see any.

 

I'm just basing it on watching my Scanmaster. My PCM has completely stock tables, except for the axle ratio and the fan on/off temps. But, since it doesn't run the engine any more (other than idle speed, VSS, fuel pump and fans), its got a few codes, including DTC 43 for no knock sensor. It will show a variable retard from 2-3deg at idle, up to 11deg or more under load. Now there are a lot of codes in my PCM since there's no MAF, no injectors, no AIR, no EGR, no whatevers.... so maybe its some combination of the codes that's causing all the knock retard to show up.