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didnt pass smog! engine knock sensor

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Old May 4, 2008 | 07:34 PM
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Default didnt pass smog! engine knock sensor

Well my smog failed today and the tech told me it was because of the engine knock sensor. My check engine light has been on for a few months. But my engine doesn't knock!

The tech was tellin me that my bass from the stereo setup could possibly trigger the knock sensor.......i have no idea if this is a possibility...

So he told me to clear the code and drive 100 miles without using the sound system.

what do I do? Where is the knock sensor located incase i need to swap it?

thanks
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Old May 4, 2008 | 09:23 PM
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There are 2 knock sensors and they are located in the valley pan under the intake manilold.
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Old May 4, 2008 | 09:28 PM
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You need to post what DTC (or DTCs) are set in your car. If you don't know how to display the DTC data, go here ....

https://www.corvetteforum.com/techti...D=26&TopicID=1

It is easiest to write down the codes once the car goes into MANUAL mode at the end of the automatic display. Post the ENTIRE DTC ... they look something like P1234C .... the P tells us it is a Powertrain code ... the 1234 is the code ...... (and there might be a Body 1234 so we need that leading letter) and at the end is a "C" or an "H" (sometimes both) showing if the code is Current or History.

There are two KR (Knock Retard) sensors on the engine. They are located under the intake manifold, in the engine "valley" between the heads. You would need one MONSTER stereo system for the bass notes to trigger the KR system ... but anything is possible.

The DTC will tell us what your problem is.

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Old May 4, 2008 | 09:29 PM
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Dump your codes and it should tell you which one is malfunctioning. I disconnected my harness while doing my heads, forgot to reconnect and got a 0326 or 0327, or both.

Last edited by PewtVette; May 4, 2008 at 09:32 PM.
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Old May 5, 2008 | 12:02 AM
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My engine light kept coming on for a year or more and code P0332 rear knock sensor. I replaced the sensors 3 time, the wiring harness once and the dumb thing still keeps coming on from time to time but engine runs fine. If you clear the codes you can probably drive for several hundred miles without the light coming on and you will probably pass smog test. I have gotten to the point where I just ignore it and clear codes as soon as I get to a stopping point. Good luck.
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Old May 5, 2008 | 12:21 AM
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well i erased all the codes today. so im praying it will stay off during my drive to work tomorrow (200 miles round trip). I have cleared it before and it always comes back on. So if it does go back on, ill post the codes.

The bad part is my registration is due next week!
thanks for everyones input/info
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Old May 5, 2008 | 12:34 AM
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Clearing the DTCs will do NOTHING for your emissions test but cause it to fail. The PCM needs to see ZERO emissions fail flags for a set number if drive cycles before it will allow you to pass the test. As BLACKZO6 recommended ,,,,,,read the DTCs and then post the error Codes, That will allow us to tell you what to do to reslove the problem.

Read and post the DTCs,

BC
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Old May 5, 2008 | 12:55 AM
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Originally Posted by rikhek
Different approach, get out of Kalifornia, home of Pelosi, Boxer and Feinstein. Move to America.

Rick


Or as I refer to it... The People's Republic of California. And I live here!
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Old May 5, 2008 | 01:44 PM
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Well I made it about 70 miles today until the light went on. I parked to get gas, then when i started her back up, the light came on.

here are the codes it shows...

10 PCM P0327H C

B0-RFA C2110H C

So what are these and what should i do?

thanks.
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Old May 5, 2008 | 08:09 PM
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Originally Posted by 97C5driver
Well I made it about 70 miles today until the light went on. I parked to get gas, then when i started her back up, the light came on.

here are the codes it shows...

10 PCM P0327H C

B0-RFA C2110H C

So what are these and what should i do?

thanks.
P0327 indicates that the FRONT knock sensor is providing a signal voltage lower than expected.

This could be due to a wiring problem to the sensor, or a sensor that is loose or overtightened, or a bad sensor.

Part number for a new sensor is 10456222 for a 1997.

C2110 is your Right Rear Tire Pressure Monitor is not transmitting tire pressure data. You need to replace the sensor in the wheel. This will not affect your smog check, but will get rid of those annoying SERVICE TPMS messages on your DIC.

Part number for a new sensor for a 1997 is

10438853 - sensor
15234846 - nut
25715243 - grommet

You should get a new grommet ... you can re-use the nut. If you haven't replaced sensors before this the batteries are coming to the end of their lives .... you will probably have other sensors go out in the near future ... you might want to consider replacing all 4 now.

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Old May 5, 2008 | 11:18 PM
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Originally Posted by EDenney


Or as I refer to it... The People's Republic of California. And I live here!
Names are nice, Most of the World considers the rest of the united states "Fly-over country".
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Old May 6, 2008 | 12:30 AM
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Originally Posted by BlackZ06
P0327 indicates that the FRONT knock sensor is providing a signal voltage lower than expected.

This could be due to a wiring problem to the sensor, or a sensor that is loose or overtightened, or a bad sensor.

Part number for a new sensor is 10456222 for a 1997.

C2110 is your Right Rear Tire Pressure Monitor is not transmitting tire pressure data. You need to replace the sensor in the wheel. This will not affect your smog check, but will get rid of those annoying SERVICE TPMS messages on your DIC.

Part number for a new sensor for a 1997 is

10438853 - sensor
15234846 - nut
25715243 - grommet

You should get a new grommet ... you can re-use the nut. If you haven't replaced sensors before this the batteries are coming to the end of their lives .... you will probably have other sensors go out in the near future ... you might want to consider replacing all 4 now.


thanks for the info! im not worried about the tire pressure sensor.....but the knock sensor-----DAMN! That sounds expensive to have replaced. Im not to sure I wanna get into pulling the manifold myself. How hard is the sensor replacement and is there anything to check before i go that route?
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Old May 6, 2008 | 07:12 AM
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Originally Posted by 97C5driver
thanks for the info! im not worried about the tire pressure sensor.....but the knock sensor-----DAMN! That sounds expensive to have replaced. Im not to sure I wanna get into pulling the manifold myself. How hard is the sensor replacement and is there anything to check before i go that route?
Removing the intake manifold isn't difficult, just time consuming. The manifold can be removed with the fuel rails still attached to it, along with throttle body. You will need to disconnect electrical connections (MAP sensor and Knock Sensors), fuel connections, throttle body to air bridge, and remove PCV pipes. Also you should replace the intake manifold gaskets (kit part number 12533587 - contains 8 gaskets) when you re-install the manifold.

Once the manifold is off replacing the sensor is a 3 minute job .... disconnect electrical connection ... unscrew ... and screw in new sensor ...(tighten to 15 lb/ft)

Call your dealer/service shop and get a quote on replacing the knock sensor .... that will help you decide whether you want to do it yourself or not.

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Old May 6, 2008 | 07:20 AM
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Originally Posted by Bill Curlee
Clearing the DTCs will do NOTHING for your emissions test but cause it to fail. The PCM needs to see ZERO emissions fail flags for a set number if drive cycles before it will allow you to pass the test. As BLACKZO6 recommended ,,,,,,read the DTCs and then post the error Codes, That will allow us to tell you what to do to reslove the problem.

Read and post the DTCs,

BC
Don't ya just love it. It's a never ending cycle.

1. Ask for advice.

2. Ignore advice, and do it your own way.

3. Come back and ask for more advice.

4. Follow original advice.
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Old May 6, 2008 | 07:52 AM
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If the sensors aren't rusted from water infiltration, thay can go bad by the seals in the bottom letting oil in. My rear sensor went bad, I replaced both sensors, the wiring pigtail that connects them both to the outside and the oil seals on the bottom. Did it off/on over the weekend part time between mowing the lawn and doing other chores. Take your time and DON'T forget the vacuum lines on the rear of the manifold. Kind of wish I relocated the oil pressure sensor at the same time. Mine's OK but it's probably enevetable it will eventually freak out.
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Old May 6, 2008 | 07:55 AM
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Intake manifold removal is a cake walk! If you or any one has ever WASHED the engine, that could explain the knock sensor issue. The sensor sit in a well and water can leak in to the well that they sit in and cause them to fail.

I recommend removing the intake and examining /repairing the sensors. It isn't as difficult as it sounds.

BC
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Old May 6, 2008 | 01:25 PM
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Ive gotta do mine too, and i was told that the wire harness to the knock sensors are brittle?
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Old May 6, 2008 | 01:44 PM
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Originally Posted by buoniconti81
Ive gotta do mine too, and i was told that the wire harness to the knock sensors are brittle?
Yes they do. I just saw mine for the first time during my heads cam swap and the wires were not as pliable as I would have liked them to be. They were also turning different colors. Part of the green wire was a very light green. The wires were whole and not cracked so I left them alone.

If I had a bad knock sensor harness, I would just rewire it myself. Hell,,it's only has TWO wires to a two wire connector.
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Old May 6, 2008 | 01:54 PM
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ok it sounds like i might have to tackle it myself. any write ups on this by any chance?

i wonder how much the sensors are....... and yes i have washed the engine i won't be doing that ever again.


thanks for the helpful input. and those with the bs comments, thanks for polluting the thread.
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Old May 6, 2008 | 11:10 PM
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