got both knock sensor codes after header and motor mount install
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got both knock sensor codes after header and motor mount install Curious if this has happened to anyone. After replacing stock exhaust with headers and off-road Y, as well as motor and trans mounts, I've received the dreaded 327 and 332 codes. After some research, it appears that the knock sensors are now reacting to different engine harmonics causing them to read low and setting the codes. Curious to see if this is common.
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The odd thing is that exhaust not hitting anything - I didn't touch the KS wiring, at least I don't think I did as the wires are all back behind the engine at the intake manifold. They are urethane motor mounts (and were a real pain to replace). Is this common with motor mount replacements? These codes (327 and 332) occurred after I finished the install. Since then, I've replaced PCM with Frost tune, and the codes recurred.
so if you clear them they come right back?
it could just be coenicdienc. Or when you jacked the engine up it damaged the wiring harness somehow.
but if you clear the DTC and it comes back immediately with out starting it, you are going to have to pull the intake and go from there.
it could just be coenicdienc. Or when you jacked the engine up it damaged the wiring harness somehow.
but if you clear the DTC and it comes back immediately with out starting it, you are going to have to pull the intake and go from there.
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so if you clear them they come right back?
it could just be coenicdienc. Or when you jacked the engine up it damaged the wiring harness somehow.
but if you clear the DTC and it comes back immediately with out starting it, you are going to have to pull the intake and go from there.
it could just be coenicdienc. Or when you jacked the engine up it damaged the wiring harness somehow.
but if you clear the DTC and it comes back immediately with out starting it, you are going to have to pull the intake and go from there.
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OK, looked at wiring in the rear of engine and it looks OK, but don't know if the wiring on the driver's side rear is associated with knock sensors. Cleared the codes, took car for a drive, and the SES light did not come on the first trip. After stopping car and then restarting, the codes returned, two of each.
OK, looked at wiring in the rear of engine and it looks OK, but don't know if the wiring on the driver's side rear is associated with knock sensors. Cleared the codes, took car for a drive, and the SES light did not come on the first trip. After stopping car and then restarting, the codes returned, two of each.
The code showed up the second time because it's probably set to report the DTC after seeing it twice. If you clear the codes, shut the car off, turn it back on, it should show the code in pending, but won't turn the CEL on.
There's a way to test the knock sensors and circuit without pulling the intake.
Disconnect the knock sensor harness at the rear of the intake, using a DVOM, check the resistance from the negative battery terminal to each wire on the knock sensor harness.
I can't remember what the value is, I can look it up later. What I would look for is if both circuits show the same or similar resistance or an open circuit. I'm guessing one of the two are going to be open(broken wire)
There's a way to test the knock sensors and circuit without pulling the intake.
Disconnect the knock sensor harness at the rear of the intake, using a DVOM, check the resistance from the negative battery terminal to each wire on the knock sensor harness.
I can't remember what the value is, I can look it up later. What I would look for is if both circuits show the same or similar resistance or an open circuit. I'm guessing one of the two are going to be open(broken wire)
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Thank you so much for the assistance. I've got a DVOM, so will give it a shot and report back.
There is this thread - aways down shows the testing procedure and readings.
https://ls1tech.com/forums/pcm-diagn...w-voltage.html
There is this thread - aways down shows the testing procedure and readings.
https://ls1tech.com/forums/pcm-diagn...w-voltage.html
Last edited by xny1989; Jan 14, 2021 at 12:57 PM.
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OK, found the problem. The wires after the KS connector have been sheared off.So, now to figure out how to rewire.
Last edited by xny1989; Jan 16, 2021 at 03:21 PM. Reason: changed info.