what does a knock senser do?

 

It senses spark knock.

It's basically a little microphone, tuned to the specific band of audio frequencies that spark knock makes in a particular bore diameter.

 

I don't know about a knock sensor ( well actually I do )

but my "Too Long of a signature sensor" Is off the charts.

 

ya, so is my AHOLE sensor...

 

That's a good way to get your questions answered.

 

I set that one off alot.

 

Bort62 your like a child.
if you don't have anything nice to say stay out of the dam thread

 

Yeah.... um what were we talking about? Oh yeah, the knock sensor. Right, it's essentially a crystal microphone or piezoelectric device as far as I know - like the old ceramic phono cartridges. Like RB83L69 says, when the engine 'pings' the computer hears the signal coming from the knock sensor and knows to retard the ignition timing.

I'm into electronics, so I kept the knock sensor off the 2.8 V6 that I pulled out of my Firebird. I meant to experiment with it to see what kind of signal comes off it etc... but haven't done anything with it yet. For one thing I think it has metric threads so it won't go into the 283 easily.

Apparently piston slap and other mechanical problems can be mistaken for knock by this sensor and cause troubleshooting difficulties.

I have a plan to amplify the signal off the sensor and if the signal is properly processed and amplified it could light up a warning light on the dash or something along those lines under knock conditions. Good for guys like me running old school carburetor / non-computer stuff to warn of preignition.

 

They tell your ecm computer when pistons rattle in bore and retard timing till it quits

 

oh ok, thanks.

 

I'm an idiot and just realized that we're talking about Knock sensors... not 02 sensors.

I shouldn't be allowed to post until after I have a coffee in the morning. Anyway, the knock sensor is specific for every different engine size.

 

I have a question does the knock sensor actually go into anything? I wanna know because I cant find the right size plug but Im getting rid of it on my new engine...does the hole need to be plugged?

 

You know, we used to call the hole the knock sensor goes in the block drain. Of course since noone actually bothers to flush their cooling system or anything (especially on 10-20 year old cars, why would you need to do that?) i guess that detail gets lost and a once important and functional feature of the ancient SBC gets renamed the knock sensor hole.

Sad really

BTW, FU-Q, some would say that it's pretty childish to put a half page picture of a plain jane base model V6 bird in one's sig. I promise if your sig said 'White 90 V6 firebird' i would have known exactly what your car looked like (well except i would have imagined it didn't have those ugly base model rims....but i digress)

 

I think the reason for his sig is to show his car and conveniently get his message, "eat rice.." across. Probably not very useful in the general forum, but cut him some slack guys - he only showed it once, and it's only 25k. A lot of smaller sig pics are actually larger in size, and you know it's small compared to some others.

 

It's a transducer tuned to sense mechanical vibration in the 6-8hz region.

 

i can see im gonna have nothing but problems with this sig so i changed it... better know?

 

Yea, better.

As for the threads, are you sure they are metric? Maybe its a 2.8 thing, but on the V8's they are std. thread. Like Ed said, goes in the block drain hole. A 283 should have a couple of those.

 

You and me both, brother. I'm not allowd to operate motor vehicles or heavy equipment without first having at least two cups.

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Ed,

I still drain the case on the sides when I flush. That's where all the mud accumulates, so is naturally the best place to drain. It's usually a PITA to get the plugs out for the first time, since the factor apparently uses nothing but LocTite on them. Once they're loosened and teflon treated, they get a lot easier.

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And as a general note to those who don't want to see those long signatures, you do have the option in your user control panel to turn off the signatures. That could be detrimental, however, since sometimes they are actually used for useful information that could be vital to answering posts correctly.

 

About the sigs. like you said Vader, turning them off is an option, but then you will miss tons of relevant info, just to filter out the trolls and kids. IMO we'd be better served to discourage vetteforum-itis and make sure people with big dorky sigs get the ridicule they deserve. Esp. being a tech only board, i see NO merit in big obtrusive sigs or pics in sigs.

 

ya well i guess im a good example,
that was my first sig, i really didn't notice how big it is becouse of the resolution im running, but i still don't think it's dorky...

 

Pleas dont lock this thread. I want everyone to think of what they say to people who ask for your help. Bort 62 is like a child he rarely has anything constructive to say and he fails to realize the reason why this forum is here. Just to remind you BORT, the board is to share experineces and knowledge not to criticize some one for the lack of. I do however question your knowledge all of the time since all the threads I have read with your reply have nothing to contribute but criticism, sarcasm. People learn quickly who to take advise from there professionalism and knowledge. I thank the guys like EDE and Ed Maher, Vader and RB83l69.