Should I replace the engine knock sensor
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Should I replace the engine knock sensor
'99 Express 1500 5.7L. Light came on last night saying 'service engine soon'. Local mechanic advises its the engine knock sensor and wants $300 to fix. Don't care about the price; care that I don't want amateurs removing the manifold. So,..
How do I know if its the sensor or if there really is an engine knock no one can hear yet? This is the van that got trans fluid in the cooling system. Possible consideration.
Thanks all!
How do I know if its the sensor or if there really is an engine knock no one can hear yet? This is the van that got trans fluid in the cooling system. Possible consideration.
Thanks all!
Last edited by mountainmanjoe; Feb 6, 2023 at 6:53 PM.
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what was the exact diagnostic trouble code please, and what were the recorded conditions (freeze frame data)?
This is all pretty important information for diagnosing the condition than a non-amateur should not ignore, as there are many causes for knock.
This is all pretty important information for diagnosing the condition than a non-amateur should not ignore, as there are many causes for knock.
Last edited by mountainmanjoe; Feb 6, 2023 at 7:01 PM.
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P035 I think. ‘Helpful’ shop did not write it down. Used a Bluetooth scanner. Did not hear any engine knock. That’s all I have.
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I had to call the shop again to get the code. It is P0327. I can't get an appointment (different shop) until the 15th. This website says its ok to drive like that. True?
https://www.engine-codes.com/p0327_chevrolet.html
https://www.engine-codes.com/p0327_chevrolet.html
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For your model vehicle, P0327 decodes to "Knock Sensor (KS) Noise Channel Low Voltage" . This describes a problem with the sensor circuit not the engine (that could mean the sensor itself, the wiring harness, or even a fried VCM). So, it's probably OK to drive.
Watch the videos in the link you posted. You should do what the "doctor" ordered and, using your VIN, search the NHTSA website. There may be a technical bulletin (TSB) for the issue. Water intrusion for example. It's important to read these or you'll have the same problem again soon.
The manifold may or may not need to come off, depending how it plays out. I would inspect the harness for damage first before going in. (nicks in wires, corrosion in connectors, too close to spark wires, etc.). Then I would look for the reference voltage, measure the resistance, continuity to the VCM, and scope out the signal to see what's going on. You can just tap the sensor with you a screwdriver to test the signal. Hopefully you get a competent, well equipped mechanic.
Watch the videos in the link you posted. You should do what the "doctor" ordered and, using your VIN, search the NHTSA website. There may be a technical bulletin (TSB) for the issue. Water intrusion for example. It's important to read these or you'll have the same problem again soon.
The manifold may or may not need to come off, depending how it plays out. I would inspect the harness for damage first before going in. (nicks in wires, corrosion in connectors, too close to spark wires, etc.). Then I would look for the reference voltage, measure the resistance, continuity to the VCM, and scope out the signal to see what's going on. You can just tap the sensor with you a screwdriver to test the signal. Hopefully you get a competent, well equipped mechanic.
Thread Starter
CF Beginner
Joined: Jan 2023
Posts: 6
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For your model vehicle, P0327 decodes to "Knock Sensor (KS) Noise Channel Low Voltage" . This describes a problem with the sensor circuit not the engine (that could mean the sensor itself, the wiring harness, or even a fried VCM). So, it's probably OK to drive.
Watch the videos in the link you posted. You should do what the "doctor" ordered and, using your VIN, search the NHTSA website. There may be a technical bulletin (TSB) for the issue. Water intrusion for example. It's important to read these or you'll have the same problem again soon.
The manifold may or may not need to come off, depending how it plays out. I would inspect the harness for damage first before going in. (nicks in wires, corrosion in connectors, too close to spark wires, etc.). Then I would look for the reference voltage, measure the resistance, continuity to the VCM, and scope out the signal to see what's going on. You can just tap the sensor with you a screwdriver to test the signal. Hopefully you get a competent, well equipped mechanic.
Watch the videos in the link you posted. You should do what the "doctor" ordered and, using your VIN, search the NHTSA website. There may be a technical bulletin (TSB) for the issue. Water intrusion for example. It's important to read these or you'll have the same problem again soon.
The manifold may or may not need to come off, depending how it plays out. I would inspect the harness for damage first before going in. (nicks in wires, corrosion in connectors, too close to spark wires, etc.). Then I would look for the reference voltage, measure the resistance, continuity to the VCM, and scope out the signal to see what's going on. You can just tap the sensor with you a screwdriver to test the signal. Hopefully you get a competent, well equipped mechanic.
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