88 Silverado Engine Electrical

[Ricky78045]

hey guys, i have two cables under the hood, that i have no clue where they go, i know one of them goes to the temp gauge in to the dash, but i need to know if its missing an attachment or is it functional. The first picture with my hand that cable is located behind the A/C just hanging there and I dont know where that one goes. The second picture I circled the other plug I guess goes to the temp, it reaches all the way to the drivers side with ease, also that cable is green. Anyone know where these two go?

[Hoods69BadBowTie]

The first one in your hand I believes goes down to a sensor on the side of your oil pan if I remember correctly not sure what its called though sorry. Should be like half way down. Can you get a better close up pic of that second wire at all?

[Ricky78045]

Thanks for the reply hoods, I'll get a picture asap of that other plug hopefully I can get a clear one tomorrow I'll take the camera.
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[Hoods69BadBowTie]

Hey yea went and looked at my TBI and ya that first one I was right on. Then the second looks like the temp one that goes to the divers side down by the first 2 spark plugs over there.
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[Ricky78045]

it reaches, and it would plug in, but i think that somethings missing, i have a picture of the plug it goes right into, but i need to know how it looks like and how it connects on a stock truck.

[Hoods69BadBowTie]

Hmm that's exactly what mine looks like. The green piece just slides over the temp sender on that little nub that's on the end of that sensor is the best I can explain it. You should see if you can slide it on there. If not I will go take a look at mine and get pics if I have to.

[Ricky78045]

Would you take a pic for me, just wanna make sure
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[Hoods69BadBowTie]

Yea defiantly can get ya one this weekend for sure. Do you want both of them or just the temp sensor pic?

[Ricky78045]

Both would be cool but I am curious about the temperature, although I'd like to know what that other one goes to, time for some google lol
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[motornut]

knock sensor /check the block above the edge of the oil pan pass side
where you would drain the block

the temp sensor plug slides on 90 degress to the plug(not like mine)
the little nib slids in the grove on the plug

[Ricky78045]

Thanks motornut, waiting for some parts to arrive and I'll check it out, thanks for the pics
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[Hoods69BadBowTie]

Here's a few of the temp sensor for ya finally. I can get some of that knock sensor if you still need them. Hope these help ya out.

[Ricky78045]

thanks hoods, i see how you did that with the spark plug wire, thats a great idea i can do to mine, and simple too lol, did you do the same thing to the knock sensor wire? also do you know if i bypassed my pollution pump, and my egr doesnt work, pretty much dead, would the knock sensor do any damage to the truck?

[Hoods69BadBowTie]

Yea I did that to keep it out of the way and from melting on the headers lol. I don't think it will hurt it but think it maybe might make your truck not run great. Here's something I pulled off the web for ya hope it helps.
"The 1992 to 1995 GM 350 has excellent timing capabilities. Since it uses a knock sensor the timing will advance as far as possible until the fuel knocks and then the computer will retard it until the knock disappears. There are two checks the computer follows to ensure the knock sensor is functioning. On a cold start it will immediately advance the timing until the knock sensor senses a knock and then the computer will return to the programmed curve. If the engine is above a specific temperature on start up the computer will wait for a specific period for a quick acceleration by watching the MAP readings. Once it sees the quick accel based on map readings it will quickly advance the timing again until the knock sensor records a knock. Once the computer sees this it will return to programmed timing and rely on the sensor to let it know if the timing is advanced to far. If it does not see a knock occur it will set a code letting you know the sensor does not appear to be functioning."

[Ricky78045]

Maybe that's why I'm having problems i got my parts now all I need is to go and get them on the truck and try connecting the knock sensor and the temp. I think half of my knock sensor "plug" was dangling on to dear life and has road damage, would I be able to just splice the cable together? can't wait to Get my baby up and running, I'll let you know and thanks for the info. You guys helped me ALOT thanks again
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[motornut]

Originally Posted by Hoods69BadBowTie

Yea I did that to keep it out of the way and from melting on the headers lol. I don't think it will hurt it but think it maybe might make your truck not run great. Here's something I pulled off the web for ya hope it helps.
"The 1992 to 1995 GM 350 has excellent timing capabilities. Since it uses a knock sensor the timing will advance as far as possible until the fuel knocks and then the computer will retard it until the knock disappears. There are two checks the computer follows to ensure the knock sensor is functioning. On a cold start it will immediately advance the timing until the knock sensor senses a knock and then the computer will return to the programmed curve. If the engine is above a specific temperature on start up the computer will wait for a specific period for a quick acceleration by watching the MAP readings. Once it sees the quick accel based on map readings it will quickly advance the timing again until the knock sensor records a knock. Once the computer sees this it will return to programmed timing and rely on the sensor to let it know if the timing is advanced to far. If it does not see a knock occur it will set a code letting you know the sensor does not appear to be functioning."

thats prob the prob i had with my 88 ......being it broke off
lights up when i floor it.......some estuff off I drove it trying to figure it out
noticed it hanging there doing an oil change,
but no info in any book as I bought it as an 85

[Ricky78045]

I found a knock connector online or at orielys. Haven't had money for the connector and a new knock sensor.
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[clinebarger]

Originally Posted by Ricky78045

hey guys, i have two cables under the hood, that i have no clue where they go, i know one of them goes to the temp gauge in to the dash, but i need to know if its missing an attachment or is it functional. The first picture with my hand that cable is located behind the A/C just hanging there and I dont know where that one goes. The second picture I circled the other plug I guess goes to the temp, it reaches all the way to the drivers side with ease, also that cable is green. Anyone know where these two go?

The connector in the first pic is the compressor cut-out switch connector, The switch is usually broke or not there.

The connector looks just like a knock sensor plug, But its black not white.

[Ricky78045]

Thanks cline, would you have a pic of where it goes? I'm assuming mines either broken or stolen (shady mechanics here in the city).
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