Knock sensor on a carb'd TBI engine

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VAL

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So I'm up underneath my truck just lookin' around, and I come across the knock sensor, the insulation on the wire frayed off, and was touching up against the rear cap of the starter. I moved it away. Question is, being that its carb'd with no computer, do I really need it? And if I do, what's it function? and how to test it?
I've read that its like a microphone of some sort for the engine.
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gpmorgan

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You don't need it if the ecu is not hooked up. It controlled engine timing if sensed an engine labor knock.
 

Swims350

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you sure there's no computer? even on carb'd motors they have some ecu for spark knock and crap, if that's got and no esc dist. then unhook or remove it.

esc dist. is easy to spot, looks like a reg. hei dist. but has a big 4 pin weatherpak connector on the side and a L-shaped plugin where the main coil hot plugs into.
 

VAL

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I have a regular HEI dizzy.
 

Swims350

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unhook it then or even remove it.
 

gpmorgan

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If you remove it I think you'll need a plug because it taps into the water jacket. With the old style HEI you don't need it. Just Un plug or leave it the way it is.
 

Swims350

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yes you definitely do need a plug to remove the sensor itself it's where the other side or older blocks have a plug to let you drain the block.
 

The dons

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My esc box is completely gone. And everything that has to do with fuel spark has been replaced to new. I have a 86 gmc c 10 carb swapped , but the motor is a 89 and it still runs bad after about 2mins the timing moves itself idk wut to do if anyone knows what I'm missing please help
 

Bextreme04

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My esc box is completely gone. And everything that has to do with fuel spark has been replaced to new. I have a 86 gmc c 10 carb swapped , but the motor is a 89 and it still runs bad after about 2mins the timing moves itself idk wut to do if anyone knows what I'm missing please help

86 would have been carb from the factory... right? '87 was the first year for TBI. Do you have a vacuum advance can on the distributor? Is it an ESC equipped distributor? Whats your vacuum and rpm doing when your timing is moving around? Is it surging in one direction or is it moving all over the place? Videos or pics are always helpful.
 

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