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Knock Sensor Replacement

clemsonfan1992

Full Member
Joined
Sep 23, 2008
Messages
225
Location
Lexington, SC
I did search on the site to try to find a step by step guide to change them out and didnt find one. But i searched the net the other day and found a guide and couldnt remember where i found it. So if anyone could hook me up with a guide that would be great! Im gonna change both of them while im in there. What materials do i need to get started and get these suckers changed out.
 
O.K. I am assuming that you already have the intake Manifold off. If you do then you will see two rubber plugs in the valley directly underneath the Intake Manifold .They have a wire coming out of the plug,which in turn connect together and go to a plug that can be removed prior to removing the intake, it should be located somewhere between the master cylinder and the driver side of the engine (you looking at the engine from the front of vehicle). Pull the plugs (carefull as you pull them, the wire should move through the grommet). you will see what looks like gray plugs connecting to the knock sensors.The easy way to take them off is by using a long Needle nose pliers or two screw drivers(what you are trying to accomplish is squeezing the plug to remove it,it should come off very easy). once you have it off the sensors are there for you too unscrew off. (y) Hope this helps.#7

I just found this after I posted this so, this might help. :cool:#7
http://www.chevyavalanchefanclub.com/cafcna/index.php?PHPSESSID=1889d62be6be3385a72c856741bd39a4&/topic,44372.msg717380.html
 
#7 I don't think clemsonfan in up for this, but clemsonfan correct me  if I'm wrong.
 
MS03 2500 said:
#7 I don't think clemsonfan in up for this, but clemsonfan correct me  if I'm wrong.
I hear ya B. Personally I would like to know why he would be changing them ???.cause I mean with all that I've done with my AV, I've used the same ones from my 5.3, and They're still working.Well hopefully he sheds light on this qusetion. (y)#7
 
Old No.7 Avalanche said:
I hear ya B. Personally I would like to know why he would be changing them ???.cause I mean with all that I've done with my AV, I've used the same ones from my 5.3, and They're still working.Well hopefullt he sheds light on this qusetion. (y)#7

Maybe a leak on the intake. Opps who said that not me >:D

OK I'm going to bed
 
Yeah I just like replacing parts 4 no reason. Cause i rather spend my christmas money replacing the knock sensors than buying something else. Well the CEL came on the other day and i got the code low voltage on knock sensor bank 2. And im ideling at around 500 which isnt normal.  So now I have to change them before the engine f's up. So correct me if im wrong.  :cool:
 
What code did you get. The sensors are under the intake and getting to them is a lot of work.
 
I dont Remember what code the machine gave me. I Just remember the low voltage on Knock Sensor Bank 2 message. But a family friend is fixing it 4 me now. I bought both sensors for 95.xx$ and he said he'll fix everything for 200.00. I just dropped it off at the shop and the intake is problly being dissassembled as I type this.
 
Let me give you some advice.

If you are not mechanically inclined and you are not willing to buy a Haynes manual, then do not attempt to do this repair by yourself.

There is a online link - from Haynes for doing repairs, but I do not know if this is one of them.  http://www.haynes.com/video.downloads

The problem lies in the fact that there is many wires in the harness and there is many connectors that has to go back on the same connector it comes off.

You have to label every wire you take off.

Then there is tools that you must have including a inch lbs torque wrench.

I highly doubt if you have a $100 torque wrench that is in inch pounds - not foot pounds.

It seem's to me that you want everything handed to you - because you are unwilling to even go to the public library to see if there is a manual that you can copy to get the repair instructions.

Parts needed includes a full set of tools, a torque wrench, a wiring harness for the knock sensors, 2 knock sensors, a couple of tubes of Permatex? Sensor-Safe High-Temp RTV Silicone Gasket, a new intake manifold gasket, a jug of anti freeze, a tool to remove the fuel line.  I would also suggest that you change the oil while you are under the hood.

The repair will involve building a mountain of Permatex on top of the valley where the knock sensors are to divert the water away from the sensors.  Sealing the sensors under the valley pan and also removing the foam from under one end of the intake manifold.  Some people say remove it and some people don't.

I would also suggest that you do not power wash the engine.  That is usually the cause of the water getting under the intake and into the sensor area.

You will need a roll of paper towels to sop up the water inside the bore where the sensor is located.  You will also need shop air and maybe a vacuum-cleaner to get the water and corrosion out of the bore .
 
Monte Carlo Man looks like im gonna have to put you in your place again!

1st off read the whole thread and you would of seen This:
clemsonfan1992 said:
I dont Remember what code the machine gave me. I Just remember the low voltage on Knock Sensor Bank 2 message. But a family friend is fixing it 4 me now. I bought both sensors for 95.xx$ and he said he'll fix everything for 200.00. I just dropped it off at the shop and the intake is problly being dissassembled as I type this.
2nd: Sorry but my library dosen't have repair manuals for cars.
3rd: BTW Autozone, Advance have a loan a part service, and they do have a inch pounds torque wrench. I checked on that when I bought the sensors.
 
Asking for advice from people is not the same thing as asking to have everything handed to you. It makes perfect sense to ask a question on a forum like CAFCNA before doing a job like this.

I replaced both of mine like two weeks ago. They were DESTROYED while off-roading. There was so much mud and crap under the intake manifold that it wasn't even funny. Not a pretty sight.

Clemson, this job is a bear. There are a ton of wires and hoses and your fuel rails with all you injectors on top of your intake manifold. It took me two afternoons but most of my work was cleaning mud/sand/dirt off of the engine and out of the cylinders.

Not a bad idea to have some else do it for you. Hope everything works out well.
 
thomsen05 said:
Why is MCM always so RUDE?  :banhim:    sorry to  :jacked:   but holy SH!T

Because the rest of the world, excluding MCM, is ignorant about vehicles, period. My conclusion, after being on this forum for a couple of years now, is that MCM either used to be or is a mechanic by trade and enjoys condescending anyone with less automotive knowledge. God forbid they have knowledge outside of the automotive world. That is just irrelevant and bone-headed crap, anyway. Medicine? Ha! For sissies! Information technology? Useless! Logistics? Pffft!

I almost suspect he would be one of those people that hates the fact that someone can get such help and instruction for free, as in, he is not getting paid to do it. Maybe forums steal a little bit of his Kool-aid, so to speak. All you have to do is mention an automotive forum to an arrogant mechanic and he/she will flip their lid. I've done it many times and get lashed. "Bah, you need ta pay a real mechanic to install those wiper blades. You sure you installed that fuel filter in the correct direction? Probably not! Cold air intake? Better get that installed by me or you'll throw a code!"

 
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