Question about sensor

I was replacing my header gaskets on the 4.3 the other day, and on the driver side of the engine block there is a sensor that screws straight into the block and off of it is the plug. I was trying to get to one of the header bolts, so i went to unscrew it to get it out of my way. Little did I know that when I unbolted it from the engine block, massive amounts of liquid started to pour out of the side of the engine. It reeked of coolant, but was not did not appear to be the orange kind i use. It was somewhat dark in the engine bay but i made it out to be a light tint of blue or purple. It may have been the lighting in the garage. I was able to get the bolt back in very quickly and it seemed only about a quart or so of fluid came out. My question is, is this a knock sensor? Or maybe some type of coolant sensor?

do you have a block heater?

<div class='quotetop'>QUOTE(02CHEV &#064; Nov 27 2006, 09&#58;33 AM) [snapback]74659[/snapback]</div>

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do you have a block heater?
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Sorry for the ignorance but what is that? Are you referring to my heater core? Or something actually on the block of the engine?

Sounds like your knock sensor. And yes, that would be coolant running down your driveway.

<div class='quotetop'>QUOTE(duckysbht &#064; Nov 27 2006, 10&#58;02 AM) [snapback]74663[/snapback]</div>

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Sorry for the ignorance but what is that? Are you referring to my heater core? Or something actually on the block of the engine?
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sorry for not makin it clear and no not ur heater core it was on block :thumb:

You know, the old coolant for these vehicles was supposed to be orange so you knew you had the right stuff. Now we have a green coolant that is universal for old and new vehicles. What color does orange and green make if you mix them together? Purplish blue has got to be close.

That seems to be the actual coolant temp sensor that the pcm uses for its coolant temp. The one for the gauges is located in the drivers side head.

how do u flush the entire coolant system then? if that has mixed coolant, wouldn&#39;t it be bad?

Mixed coolant shouldn&#39;t hurt anything. Mosts coolants you buy are compatible with dexcool.

<div class='quotetop'>QUOTE(Allstar55566 &#064; Nov 27 2006, 09&#58;03 PM) [snapback]74740[/snapback]</div>

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how do u flush the entire coolant system then? if that has mixed coolant, wouldn&#39;t it be bad?
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You can go to wal mart or autozone and buy a kit for like 15 bucks. I used it on my s10. It basically taps into the heater hoses located on the firewall, and then you hook up a garden hose to it, start the engine and open the tab underneath the radiator. Once you open that, turn on the hose, and start the truck up, it will start flushing it out. I just followed the directions, and when i was doing it i could see all the dirt and grime coming out of the nozzle attached to the heater hose. it works really well and cleans it out pretty good.