DTC P0327 Knock Sensor Circuit Low Voltage
#1
DTC P0327 Knock Sensor Circuit Low Voltage
I've searched the forum without any definitive answers so I'm hoping someone here can give me a diagnostic procedure or flow chart to fix this recurring problem.
Here's the situation:
After a few minutes to a half hour of driving, the DTC described above is recorded. Pretty soon the SES light comes on. Scanning always shows DTC PO327 Knock Sensor Circuit Low Voltage (SES) (OLD) (CURRENT) (IMMATURE)
I can scan and clear the code with HP Tuners allright but the strange thing is when it throws the code the KR goes to 3 and stays at 3 KR even at idle. If I disconnect the knock sensor connector while actively scanning the KR still reads 3!
VCM voltage reads 13.5 on HP Tuners while scanning.
1. If it's a bad sensor like some of the other threads regarding this DTC talk about, why doesn't the live-scanned KR change when the sensor lead is unplugged?
2. If it's a bad circuit, how do I trace the fault?
3. Is there something I've missed?
Here's the situation:
After a few minutes to a half hour of driving, the DTC described above is recorded. Pretty soon the SES light comes on. Scanning always shows DTC PO327 Knock Sensor Circuit Low Voltage (SES) (OLD) (CURRENT) (IMMATURE)
I can scan and clear the code with HP Tuners allright but the strange thing is when it throws the code the KR goes to 3 and stays at 3 KR even at idle. If I disconnect the knock sensor connector while actively scanning the KR still reads 3!
VCM voltage reads 13.5 on HP Tuners while scanning.
1. If it's a bad sensor like some of the other threads regarding this DTC talk about, why doesn't the live-scanned KR change when the sensor lead is unplugged?
2. If it's a bad circuit, how do I trace the fault?
3. Is there something I've missed?
#2
Originally Posted by SoCal Goat
I've searched the forum without any definitive answers so I'm hoping someone here can give me a diagnostic procedure or flow chart to fix this recurring problem.
Here's the situation:
After a few minutes to a half hour of driving, the DTC described above is recorded. Pretty soon the SES light comes on. Scanning always shows DTC PO327 Knock Sensor Circuit Low Voltage (SES) (OLD) (CURRENT) (IMMATURE)
I can scan and clear the code with HP Tuners allright but the strange thing is when it throws the code the KR goes to 3 and stays at 3 KR even at idle. If I disconnect the knock sensor connector while actively scanning the KR still reads 3!
VCM voltage reads 13.5 on HP Tuners while scanning.
1. If it's a bad sensor like some of the other threads regarding this DTC talk about, why doesn't the live-scanned KR change when the sensor lead is unplugged?
2. If it's a bad circuit, how do I trace the fault?
3. Is there something I've missed?
Here's the situation:
After a few minutes to a half hour of driving, the DTC described above is recorded. Pretty soon the SES light comes on. Scanning always shows DTC PO327 Knock Sensor Circuit Low Voltage (SES) (OLD) (CURRENT) (IMMATURE)
I can scan and clear the code with HP Tuners allright but the strange thing is when it throws the code the KR goes to 3 and stays at 3 KR even at idle. If I disconnect the knock sensor connector while actively scanning the KR still reads 3!
VCM voltage reads 13.5 on HP Tuners while scanning.
1. If it's a bad sensor like some of the other threads regarding this DTC talk about, why doesn't the live-scanned KR change when the sensor lead is unplugged?
2. If it's a bad circuit, how do I trace the fault?
3. Is there something I've missed?
After reading the diagnostic procedure for PO327 DTC I realized that once the PCM finds a fault in the knock sensor circuit, it automatically retards timing 3-4 degrees as a safeguard against detonation until the fault is corrected and cleared.
That explains my questions 1 and 3.
#3
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I know this is a super old post, but I have this same issue and I have replaced both sensors and the harness from the sensors to the plug on the intake (truck engine) and there is nothing wrong...any other ideas guys.