67Motorcat

Well I finally got the dreaded PO327 and PO332....

Can't really complain too much with over 200K on the clock but,

I replaced both sensors and the harness yesterday and cleared the codes.
Meticulously cleaned everything and reassembled correctly.

Today they came back on,same codes,WTH?? Cleared again and same result,back on.

Used GM sensors and harness.Truck runs fabulous but this is not good.

Advice please.

67Motorcat

I should probably add that I did in fact put a small dab of anti-sieze on the threads of the knock sensors.

Creature of habit,but I would assume when torqued correctly would not interfere with continuity.

Correct me if I'm wrong....

Really has me puzzled.

Fishinfooleric10@aol.com

May not have had the actual 02 sensor bad, it could be you are getting a short somewhere or bad connection. As I am sure you know, the 02 sensor send signals back and if the volts aren't just right it can throw a code and that may be your problem. I am not positive on the electrical readings but I remember reading something the other day about how to do it and the reading you should get. I hope this maybe gives you an idea of why you keep throwing the code.

Fishinfooleric10@aol.com

Whoops sorry man I realized as soon as I clicked out that your knock sensors were giving you the problems not the 02 sensors. Sorry about that, but anyways I would do the same exact thing actually. Anytime I can't seem to come up with answer like you got right now, I just try to look at all wires because you may have a bad connection or wire.

67Motorcat

Thanks anyway for the response .

I believe I'm supposed to get 5 volts at the connecter with the Key on.I'm getting .7 volts.

So not really sure whats going on.The knock sensors were toast for sure so those had to go anyway.

I have a appointment with my speed shop,RPM Motorsports,on April 1st to do some data logging to actually see whats going on.

It may be a simple as desensitizing the knock sensors a bit and run premium fuel exclusively or possibly the ECM could be having issues.

Truck runs just fine as usual....could also be I guess the sensors were damaged during shipping but doesn't jive with low voltage.

I report back my findings

fursty

Circuit Description
The knock sensor (KS) system detects engine pre-detonation. The powertrain control module (PCM) retards the spark timing based on the signals from the knock sensors. The knock sensors produce an AC voltage when specific frequencies are detected. The knock sensor voltages are an input to the PCM. The amount of AC voltage produced is proportional to the intensity of the knock.

An operating engine produces a normal amount of engine mechanical vibration. The knock sensors produce an AC voltage signal from this noise. When an engine operates, the PCM learns the minimum and maximum frequency of the noise that the engine produces. When the PCM determines that this frequency is less than or more than the expected amount, a knock sensor diagnostic trouble code (DTC) sets.

Conditions for Running the DTC
The engine speed is between 1,500 RPM and 3,000 RPM.
The MAP is less than 44 kPa.
The engine coolant temperature (ECT) is more than 60°C (140°F).
The throttle angle is more than 0.5  percent.
The engine run time is more than 20 seconds.
Conditions for Setting the DTC
The PCM determines that this frequency is less than or more than the expected amount for less than 3 seconds.

Action Taken When the DTC Sets
The PCM illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the PCM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the PCM records the operating conditions at the time of the failure. The PCM writes the conditions to the Freeze Frame and updates the Failure Records.
Conditions for Clearing the MIL/DTC
The PCM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
A last test failed, or current DTC, clears when the diagnostic runs and does not fail.
A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
Use a scan tool in order to clear the MIL and the DTC.
Diagnostic Aids
Important: Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM connector gaskets when diagnosing or replacing the PCM. Ensure that the gaskets are installed correctly. The gaskets prevent water intrusion into the PCM.

Check the knock sensor for proper installation. A knock sensor that is loose or over torqued may cause the DTC P0327 to set.

If DTCs P0327 and P0332 are set at the same time, inspect for poor connections at the KS harness jumper, located at the left side of the intake manifold.
(From GM Service)

Measure the resistance of the appropriate knock sensor using the DMM connected to battery ground. 93–107K Ω

Hope this helps!!

67Motorcat

Thanks Firsty!

Yeah,I read all that on the OBII web-site.