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Discussion Starter · #1 ·
i know they seem to be a pain in the ass
are they any TSBs on them
its the knock sensor circuit 1 low imput code
does anyone know why this happens ive heard its common is it the sensor or wiring
where is it and what voltage should it be putting out?
 

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HOT AIR BALLOON OWNER
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It's the sensor, they're easily fucked up by moisture.

Just replace them and motor on. A TSB isn't going to do anything for you, it's not like GM will replace them free. :rofl2:
 

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Discussion Starter · #3 ·
It's the sensor, they're easily fucked up by moisture.

Just replace them and motor on. A TSB isn't going to do anything for you, it's not like GM will replace them free. :rofl2:
no not like a recall it just knew it was common and was wondering if it was common the wires corroded or break or if the sensors fail
so i should start with replacing the sensor?
 

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I replaced the harness and the sensors in my truck everything omh'd out like it was suppost to and everything and it still throws the same low input codes so I just shut them off in the tune
 

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not a bad install. just tedious.
 

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GMC Owner
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Yah...they thought it was a good idea to move them from the block to under the intake....WTF!....luckily I procrastinated enough that my check engine light shut off by itself. She must have dried up a bit. I am sure I will be replacing it down the road but for now there's no annoying check engine light.
 

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Discussion Starter · #8 ·
i think im going to replace the sensor and ill check the resistance in the wires but when i take the intake off do i need a new gasket you think?
anything else i should replace while doing this pain in the a$$ job
 

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GMC Owner
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Depending on the shape the gasket is in you may be able to re-use it, but if you can I would definitely replace it.
 

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To me,it's not a problem if I know what it is. I just reset and go on my merry way. My hearing may not be what it used to be, but if it's knocking I will hear it. If I ever have to dig into my top end I'll think about replacement.
 

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Honestly it is one of the easier repairs. The hardest part will be if you do not have the fuel line removal tool. They are at Autozone or whatever parts store you use.

I do not replace the foam under the intake, my thought is that water will find it's way under there and the best thing to do is make sure it gets back out, but I live in AZ where it is much drier than where most of you live. Either way when you replace the harness silicone up the plugs in the valley cover.

The other reason to just do the repair is at some point you are going to have to change the intake manifold gaskets anyway, might as well.

BTW you may not hear the knocking, the PCM will reduce your ignition timing as soon as it thinks you have knock, if the sensors are bad it may be saying there is knock when there isn't and you are getting worse performance anyway.
 
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