My question is is it the knock sensor setting this code or o2 sensor? The passenger side has a new o2 sensor in it. My car has thrown occasional knock sensor codes, but now it will not go away and performance at the track is hurting, so I believe it's cutting timing. The description of the code is throwing me off(low input), does that mean that sensor is bad, or that a bad o2 could be throwing this code(driver side o2 is older than passenger).

 

Just checked the codes again...It now threw another o2(bank 2, sensor 1) code....could this be because of the bad knock sensor? I plan on pulling the intake a little later and putting a new knock sensor in to see if that helps.

 

what did you do to fix the problem? i have been getting a code reading po327 knock 1 bank1 low input. any suggestions?

 

Just got this same code as well.... wtf

 

I got the same code today along with a failed cat code

 

Here is what I have learned since my initial posting. The Knock sensor in the LS1 is a single wire unit and diagnostics only can determine that it is reading a knock or the sensor has failed. The GM mechanic assumes if there is no additional codes the sensor must be bad. I had very bad fuel in the 99TA I bought. It hadn't been driven in 5 years and know one told me that. As a result the car knocked and had no other code so the "assume" it is the sensor. I drained the tank added new fuel and cleaned the top end and it runs like a top. The mechanics I talked to said the knock sensors rarely fail, and usually the knock sensor code is secondary to another problem. You can even have false knock. Such as a header hitting the frame and the sensor reads this as knock. Look long and hard before you pull the intake manifold to replace the knock sensor it may not be the problem.

 

All the ones I've seen the sensor gets rusted from water getting in there. Its very common on the trucks. The LS1 is the same design so probably same thing happens.

 

its funny that you say that because i just finished replacing my knock sensors. Sensor 2 was rusted, i guess the grommet didn't keep the water out at all. But to the OP i suggest you replace them both, it's an annoying fix but it's not too hard.

 

All the Gen 3's have this problem.

Easy answer is to cover them with protective grease and attempt to waterproof the rubber grommet on the valley plate also.

P0327 usually happens when the KS or the wiring has a fault, not from bad fuel.

 

The idea wasn't that you had fuel! It was that other conditions can cause you to get a bad Knock snesor code. Including mechanical contact knocks. The factory diagnosis process follows that if no other code is shown the KS is bad. The advice that knock sensors rarely fail came from a California builder and friend. Maybe they have less "rust" problems then we do in cold states. Either way I am glad I took a look at all other factors before I pulled the intake manifold. If not your concern go for it!