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Hi my check engine light is on and an OBD scanner shows Knock sensor 1 Low signal. According to my manual KS1 is on the front bank of cylinders. I replaced this last night. Cleared the OBD error, took the car for for a spin and the check engine light is back on with KS1 Low signal! I'm thinking either KS1 is on the rear bank of cylinders or I have a wiring problem. I bought 2 sensors so I'll replace the other one this weekend. It could be a wiring fault as I got a complete engine replaced under warranty last year, maybe something got stretched in the process. Just wondering if anyone else has had fun with knock sensors?? Thanks. Car is a G6 GTP 3.9L.
 

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Knock sensor location on 2006 v-6 (3.5 L)

I cannot locate the knock sensors on my engine. I have 2006 G6 with 3.5L V-6 engine. Does anyone have a picture or something that can help me? Detailed instructions would be helpful. I don't have a clue as to where to start. I was told I could change them myself but I can't even locate them.
Thanks!
 

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I cannot locate the knock sensors on my engine. I have 2006 G6 with 3.5L V-6 engine. Does anyone have a picture or something that can help me? Detailed instructions would be helpful. I don't have a clue as to where to start. I was told I could change them myself but I can't even locate them.
Thanks!
PM me with an email addy & I'll send the how-to.

But before replacing them, what code/s are you getting?
 

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So, for the benefit of the forum, this is what pint4 sent me in a PM:

"Thanks. My codes I believe were p0332 and p0327. the codes said one was ks sensor 1 and the other ks sensor 2."
 

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Knock Sensors

Yes, I did some work to the car. GM replaced the motor for the power assisted steering. We also changed both lower control arms and a wheel bearing hub. Had to jack up the engine a half inch or so to remove and replace the lower control arms. If I don't replace the knock sensors, do I just clear the check engine light and wait and see if it comes back on or should I be replacing something else.
Thanks.
 

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These are type 2 codes & would have popped very soon after the damage to the harness was done (within a couple engine starts). Can you remember exactly how much time passed between the work being done & the check engine lamp turning on?
 

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How do I know if the harness is bad? I have no idea where the Knock Sensors are located and so I have no way of following the harness if I don't know its path-start or finish. How do I find the harness so I can check it out? Wish someone had a picture so I knew where to look.
Thanks.
 

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How do I know if the harness is bad? I have no idea where the Knock Sensors are located and so I have no way of following the harness if I don't know its path-start or finish. How do I find the harness so I can check it out? Wish someone had a picture so I knew where to look.
Thanks.
Just emailed you.

There are also photos in the Chiltons for G6.

I have to warn you that you're dealing with a problem that would probably baffle many professional mechanics. Looking at the schematic, I can't find any circuit issue that would affect both sensor circuits simultaneously. They are isolated circuits all the way from the PCM. Maybe someone else has seen this one before.

Did you ever try just clearing the codes & seeing if they return?
 

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hello i have the knock sensor on cylinder 2 , low signal but it goes and comes back like a week later without clearing obd, do u think the sensor is going bad,
 

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I cleared codes and the check engine light is on again, less than 12 hours later. Looks like the problem is still there. I guess the next step is to change both sensors. Not sure I have a lot of options-codes are po332 and po 327.
Thanks.
 

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I cleared codes and the check engine light is on again, less than 12 hours later. Looks like the problem is still there. I guess the next step is to change both sensors. Not sure I have a lot of options-codes are po332 and po 327.
Thanks.
The chances that both sensors crapped out simultaneously are infinitesimally small. IMHO, that money would be better spent at a dealer (or better yet, at a good mechanics shop) on a proper diagnosis. For whatever reason, both your sensors are failing to report a signal back to the PCM.
 

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Interesting thing happened Saturday. I had to drive 70 miles at highways speeds to a nearby city for a meeting. 50 miles into the trip and I looked at my dash and the check engine light was off. 3 hours later when I started the car to return home, the check engine light was on again. Doesn't make sense that it would turn itself off and then reactivate itself. Still thinking I might replace the two sensors and go from there. I am trying to help out my daughter as it is her car. Trying to avoid running up a $500 or more in bills trying to find an elusive problem. Hoping I can solve it with the help of some experts on this site who have seen just about every kind of G6 problem. I appreciate all the help and advice.
Thanks.
 

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The reason the CEL turns off & back on is because the problem is intermittent. The tests run continuously on both circuits & sometimes they pass the test for awhile. And then they fail again (assuming here that the same two codes have popped). It's an interesting problem that has me scratching my head. For 50 bucks you can replace both sensors yourself. For 100 you can get a dealer (or better yet, a trusted mechanic) to diagnose it. You may be right & I'll end up surprised.

Without checking, you should not assume what codes are popping the lamp on. Code readers are only 20 bucks these days on Amazon.

Knock sensors must be torqued to 18 lb ft on that engine. Very important. And don't put anything on the threads.
 

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I replaced both knock sensors and still have the knock sensor codes 332 and 327. Is there something else that might be causing the low signal? The cable and connectors looked good. Could it be spark plugs, spark plug wires , etc? I did purchase a good code reader so I can read the codes and erase them.
Thanks!
 
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