Consider this...
I was throwing the P0332 while getting a tune from Justin...he told me it was the knock sensors...I replaced them...I replaced both of them...cleared the code...its been running fine...the code just came back up 2 days later....wtf???
Any help is appreciated guys!
There is not a code for broken knock sensor. There are several readings , I know this will be long but reading this can save you either a pain in the ass sat afternoon or a pricey trip to your local mechanic if you are not confident enough to do this part swap. I call it a part swap because a mechanic understands the mechanics of the parts. Don't be parts-swapers be mechanics. I dont own a Chevy but I read every forum looking for a smart cure for a low input on a knock sensor on these motors. I found none and they made no sense to me. I joined this forum to pass this info along. Here are our key hints that led me to my solution. Hint one all vehicles that are showing these codes are exposed to high concentrated of moisture. and this type is sensor is waterproof. Hint two There is only One wire from ecu to the "knock sensor". Are any of you seeing the issue here? Also Gm recommends that you use only their pricey AC-Delco sensor...and that they "dont know why" but original ac-delco works when others dont. Well... Here it is, A message sent to a client with a low circuit knock sensor code---> Hey I am sorry I did not respond earlier, I have been elbow deep in a few projects, heads up anytime you get the top of your motor wet you are going to be at risk of getting a faulty reading at your knock sensor. All gm forums and 99 percent of mechanics will tell you its a failing knock sensor. This knock sensor reading is very very common in the 2000 - 04ish models and is particularly "sensitive to water damage" at least thats what the understanding is. But I couldn't understand how the reading P0332 was reading low circuit input. Well I decided to to look into this sensors workings. I learned that they used something called a pizeo-electric sensor,(what they use in waterproof lighters, bbq grills and navy ships) Its a group of crystals that when compressed release a very small .5 volt charge. The sensors are calibrated to frequency and when certain frequencies resonate in the motor it responds back to your ECU and adjusts the air to fuel ratio to prevent the "knocking" or resonance that is causing the pizeo-electric circuit to send a charge. Here's the catch, certain GM Models (yours) runs a only one wire from the ECU to the knock sensor, It sends out 2.5 voltz to knock sensor and if it has no resistance and it would get 2.5 voltz back because the negative charge of the circuit would not have been triggered, and even if it had, it would adjust accordingly (thats its job) So Here is the thing engine ground and chassis ground on these vehicle is crucial as ECU is not set up to pass current at voltage the engine is, the knock should have its own ground return line to ensure a similar grounds and not have faulty readings. But this system relies on the fact that the block and sensor are dissimilar metals which is fine until you add H20 to the mix, a very very negatively charged compound and also connecting the wires inside the sensor the iron ground of -.3 to -.4. So we send out 2.5 and receive back only 2.2 or 2.1. (low circuit input) As we remember the chassis ground showed.00 potential difference to negative cable when the engine had a small difference . Because if the pi-sensor was engaging it would be 2.0 not 2.1 or 2.2. So most assume the sensor is bad, not a ground discrepancy. Also with the ground variance of the ecu to sensor/block what was experienced was a ground loop, and causing other functions to not operate correctly such as clock timer and other obvious ground issues. If the area is given ample time to dry or was induced into speed dry via engine heat, and ecu was cleared by removal of both terminals, and a clearing of power within the vehicle via grounding, a chassis to negative terminal connection first and then the positive cable connected, then turn the key to acc position to engage the Ecu and thus linking the ecu and knock then adding the engine ground followed by engine ignition. This should re-calibrate the ECU to knock sensor, rectifying a Po332 Code. Also see any differnce between delco and aftermarket and why they dont work?
