1slowbusa

iTrader: (8)

I had the P0327-Knock sensor circuit low voltage code pop up on my camaro about a month ago. I changed both the knock sensors and the pigtail for the knock sensors. Now after driving about 20 minutes I get P0327-Knock sensor circuit low voltage (Old) (Immature).

I can delete the code and it comes back after about 20 minutes of driving. Can anyone help me out. Is the problem corrected???

Thanks in advance

1slowbusa

iTrader: (8)

Anybody

Rhino79

iTrader: (7)

check that pin in the pcm connector. I have seen corrosion in the pcm connectors before at the location of the knock sensors and crank sensor pins. More so in the trucks than the cars, but worth a check for sure.

1slowbusa

iTrader: (8)

Thanks Rhino79, I will check

62n62

iTrader: (17)

DTC P0327 Knock Sensor (KS) 1 Circuit






Circuit Description

The Knock Sensor (KS) system detects engine pre-detonation. The 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 (noise). 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 the engine produces. When the PCM determines that this frequency is less than or greater than the expected amount, a knock sensor DTC will set.

Conditions for Running the DTC

• The engine speed is between 1,650 RPM and 3,000 RPM.

• The MAP is more than 49 kPa.

• The engine coolant temperature is more than 60°C (135°F).

• The throttle angle is greater 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/replacing the PCM. Ensure that the gaskets are installed correctly. The gaskets prevent contaminant intrusion into the PCM.

• For any test that requires probing the PCM or component harness connectors, use the J 35616 connector test adapter kit. Using this kit prevents any damage to the harness connector terminals. Refer to Using Connector Test Adapters in Wiring Systems.


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

For an intermittent, refer to Symptoms .

Test Description

The numbers below refer to the step numbers on the diagnostic table.

2 This verifies the malfunction is present. The scan tool will display DTC Ran=Yes and Pass=Int if the failure is intermittent. This indicates the diagnostic passed this ignition cycle and failed this ignition cycle. At this point the resistance of the knock sensors should be verified to be in the correct range. If the knock sensor resistances are correct, inspect the KS system wiring connections. When testing the KS system connections, start at the KS system jumper harness connector located behind the intake manifold. Then inspect the connections at the PCM. Refer to the wiring schematic for the correct connector and terminal. Then inspect the connections at the appropriate knock sensor. Failure Records data does not include the parameter KS Activity, however other parameters may aid in locating the conditions under which an intermittent occurred.


3 This test isolates the Knock Sensor from the rest of the circuit.


4 Tap on the engine block near the appropriate knock sensor. Do not tap on plastic engine components.




Step



Action



Value(s)



Yes



No




1


Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?


—


Go to Step 2


Go to Powertrain On Board Diagnostic (OBD) System Check



2


Important: If an engine knock can be heard, repair the engine mechanical condition before proceeding with this diagnostic. Refer to Engine Noise Diagnosis in Engine Mechanical.

1. Turn ON the ignition leaving the engine OFF.

2. Review the Freeze Frame and/or Failure Records data for this DTC and observe the parameters.

3. Turn OFF the ignition for 15 seconds.

4. Start the engine.

5. Operate the vehicle within the conditions required for this diagnostic to run, and as close to the conditions recorded in Freeze Frame and/or Failure Records as possible. Special operating conditions that you need to meet before the PCM will run this diagnostic, where applicable, are listed in Conditions for Running the DTC.

6. Monitor the Diagnostic Trouble Code (DTC) information using a scan tool.


Does the scan tool indicate that this diagnostic failed this ignition?


—


Go to Step 3


Go to Diagnostic Aids



3



1. Disconnect the knock sensor electrical connector located behind the intake manifold.

2. Measure the resistance between the appropriate knock sensor signal circuit (sensor side of harness) and the battery ground using the DMM.

3. Set the DMM to the 400K ohm scale.


Is the resistance of the knock sensor within the specified range?


93–107KΩ


Go to Step 4


Go to Step 6



4



1. Connect the DMM between the appropriate knock sensor signal circuit (sensor side of harness) and the engine block.

2. Set the DMM to the AC voltage scale.

3. Tap on the engine near the appropriate knock sensor while observing the signal indicated on the DMM.


Is any signal indicated on the DMM while tapping on the engine near the appropriate Knock Sensor?


—


Go to Step 5


Go to Step 7



5



1. Disconnect the PCM connector C1 located on the same side as the manufacturer's logo. Refer to Powertrain Control Module Replacement/Programming .

2. Test the KS signal circuit between the PCM and the knock sensor connector for the following:

• An open

• A short to voltage

• A short to ground

3. If you find a condition repair the condition as necessary. Refer to Wiring Repairs in Wiring Systems.


Did you find and correct the condition?


—


Go to Step 10


Go to Step 8



6



1. Remove the intake manifold. Refer to Intake Manifold Replacement in Engine Mechanical–5.7L.

2. Test for an open or a short to ground in the signal circuit between the knock sensor jumper harness connector, located at the back of the intake manifold, and the knock sensor connector. Refer to Circuit Testing in Wiring Systems.

3. If you find a condition, repair as necessary. Refer to Wiring Repairs in Wiring Systems.


Did you find and correct the condition?


—


Go to Step 10


Go to Step 7



7


Replace the appropriate Knock Sensor. Refer to Knock Sensor Replacement .

Is the action complete?


—


Go to Step 10


—



8



1. Inspect for a poor connection at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

2. If you find a poor connection repair as necessary. Refer to Repairing Connector Terminals in Wiring Systems.


Did you find and repair the condition?


—


Go to Step 10


Go to Step 9



9


Important:: Program the replacement PCM. Refer to Powertrain Control Module Replacement/Programming .
Replace the PCM.

Is the action complete?



—


Go to Step 10


—



10



1. Select the Diagnostic Trouble Code (DTC) option and the Clear DTC Information option using the scan tool.

2. Idle the engine at the normal operating temperature.

3. Select the Diagnostic Trouble Code (DTC) option and the Specific DTC option, then enter the DTC number using the scan tool.

4. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text, if applicable.


Does the scan tool indicate that this test ran and passed?


—


Go to Step 11


Go to Step 2



11


Select the Capture Info option and the Review Info option using the scan tool.

Does the scan tool display any DTCs that you have not diagnosed?


—


Go to the applicable DTC table


System OK

mjs1012

iTrader: (36)

have you replaced the sensors and harness? i had the same issue (p0332) and it needed new sensoors/harness and its good to go.

1slowbusa

iTrader: (8)

Yes i replaced the both sensors and the pigtail harness. I keep getting the code but it says it is old immature. What ever that means???

When i get time i am going to check the continuity between the harness connector that connects to the pigtail to the ECU connector.

Maybe i will find something then.

67SS509

iTrader: (25)

Did you use GM sensors or aftermarket for replacements?

1slowbusa

iTrader: (8)

I used GM sensors and GM pigtail.

This is what i have done so far to troubleshoot the new pigtail, sensors and the wiring from the Pigtail to the ECU

I connected a DMM to pin 11 and unplugged the pigtail from the harness wiring. I found continuity between both.

I did the same as above but connected to pin 51 and the other side of the connector where the pigtail connects.

I then connected the pigtail back up and read the ohms from pin 11 on the ECU to ground. I found 99 ohms.

I then did the same thing as above with pin 51 and read 97 ohms.

While reading the ohms across the sensors i also wiggled the wiring harness to see if the ohms dropped out and they didnt.

This tells me that the knock sensors and the wiring is good. Now the question is, is everything ok and what does (old) (immature) mean?? Any opinions would be appriciated.

1slowbusa

iTrader: (8)

Anybody have an opinion?

1slowbusa

iTrader: (8)

Ok so after doing everything above I replaced the wiring going to the PCM from the Knock sensor Pigtail. This did not fix the problem

I then changed the PCM and downloaded the program and 2 miles down the road the code came back.

When i got the car home i disconnected the pigtail that is located behind the intake and measured the millivolts and resistance while running. The millivolts on the rear sensor fluctuated from 70mv-100mv. The resistance on the rear fluctuated from 30k ohms to 60kohms to Overload. This was checked while the car was running.

The front sensor was the the same with the millivolts as the rear, fluctuated from 70mv to 100 mv. The resistance while the car was running was 15kohms to 50kohms but was going overload alot more than the rear.

I turned the car off and the resistance on both sensors were around 99k ohms.

This has me puzzled. Any opinions are appriciated. I have videos of the readings if anyone is interested in seeing them.

1slowbusa

iTrader: (8)

Anybody??

L-EATER

iTrader: (2)

Overtorqued/undertorqued sensor? Or perhaps the new sensor is just bad. You have pretty much eliminated everything yet the problem is still there. Now you are to the point of "grasping at straws" I would try swapping that front sensor with the old rear one you took out.

1slowbusa

iTrader: (8)

I replaced both knock sensors again. So i have replaced everything and the knock sensors twice.

I have attached a snap shot of the code I am getting. If anyone has any opinion on what i can do to fix this issue, please let me know. I torqued the sensors to 15 feet pounds.

Could the tune be causing this, I dont think it can but not quite sure???

lt1pwr1

iTrader: (1)

What about where the Knock Sensors sit in the valley tray? Maybe it is corroded and you aren't getting a good ground? IDK, seems like you have tried everything at this point.

Also, might want to look at the connector that is at the Knock Sensor harness. Maybe the wires are broken there and not the knock sensor side?

1slowbusa

iTrader: (8)

Yea I checked the valley cover and it was clean. I even replaced the male connector thats part of the wiring harness. That didnt work. I am getting the same code and last night it even threw my ses light on so the pending immature went away.

When I got the car home with the ses light on I disconnected the battery and checked the resiatance across both senaors at the pcm connector. The both read around 100k ohms.

1slowbusa

iTrader: (8)

I just saw that the front of the fast 102 intake is touching the water pump. Would this cause the knock issue? I am going to take the intake off this week (again for the like 8th time) and grind it down so it doesnt touch.

thunderstruck507

iTrader: (18)

It might be a long shot but I filled my car up with $40 worth of the shittiest gas I've ever had. The car was pulling 10* of timing and throwing a code for the bank 1 knock sensor voltage low.

I ran the tank out and then filled up with quality name brand 91 octane and cleared the code again. Car picked up like crazy and has run fine since.

MyFirstLS1

iTrader: (8)

I would inspect the entire mating surface off the intake see if it could be contacting anywhere else. Make sure it isn't pinching a wire. Do you have another intake you can throw on try that way? Possible its hitting the valley pan bolts as well ?

There is no chance the car has a slight knock you can't hear ?

MontecarloDrag

iTrader: (3)

Did you disable burst knock or did anything to the tune? I have seen this code pop when I disabled burst knock. Enabled it and the code was gone