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I'm trying to eliminate unused wires/harness's from my 1985 T/A. Long ago I put in a 350 with Edelbrock carb/intake, Mallory ignition system, and Mallory 110gph electric fuel pump.
It's an automatic(THM700R4) and has the posi diff and WS6 package.
Originally came with a 305.
What are these two 'wires' for? The top one is more like a vacuum tube; the bottom one connects to the block.
This one connects to the driver side head/block area.
What are these two items used for? They look like relays for a fuel pump but the car came with a mechanical pump and quadrajet carb originally.
Because I started another project. The other thread was specifically about the items on the driver side firewall. After getting into it more I realized I need to get rid of alot of 'junk' and clean up the ENTIRE wire harness.
If you want to strip down the wiring harness then what you do is take off the wire loom and tape and follow where wires go and actually strip down the wiring harness. Now go get to work.
* The plastic tube is indeed a vacuum line. It went to the heater control valve that lets hot water into the heater core for cab heat.
* A wire that goes to engine block is obviously a ground wire for something. You'll figure out what for when you strip down the wiring harness. Or just leave it alone.
* The little square box bolted to the lip of the cowl looks like a MAP sensor.
* And you'll figure out what the relay is for when you..... guess.... yep, strip down the wiring harness.
My guess is wires that go to a sensor are actually for the sensor that the wires go to. What do you think?
Very helpful. Thanks.
Anyone else want to chime in on what these sensors are for and if they are needed since I don't use computer controlled items on the engine any longer?
Last edited by Tidan; Jan 31, 2020 at 11:43 AM.
Reason: clarification
He is frustrated with you for the same reason I am frustrated with you: It appears as though you're putting in near 0% effort on this. And some of your questions have obvious answers. It's like I'm expecting you to post a picture of a tire and ask, What's this do?
It's just getting painful to watch and people are going to walk away if you don't show a stronger effort on your part to understand. Just change your approach a little bit and you'll get better help.
If you want to strip down the wiring harness then what you do is take off the wire loom and tape and follow where wires go and actually strip down the wiring harness. Now go get to work.
This is what you need to do. I know from my own experience with my own car that no matter how many questions I asked, or how much research I did (and I did a lot), I was never going to actually know what to do until I got dirty and dug in. The day I dug in (and it took me a while to get brave enough to do that) is the day I really began to make progress. I had few questions after that, and when I did ask a question it was very focused and targeted on a subject, which helped other people to be able to help me.
Do research, get a factory shop manual off eBay for $40, read the swap guide. ALL the answers you need are ALREADY here on thirdgen.org if you just do your own work. You're literally doing NOTHING to help yourself. You want people to hold your hand at this point. You might as well post your address and ask someone to come do it for you.
You've answered your own question, you're not using the ECM anymore. so remove "sensors" then. This isn't rocket surgery.
I know all about these cars because I read, then I read some more. Then when I am done reading that, I go read more.
Do research, get a factory shop manual off eBay for $40, read the swap guide. ALL the answers you need are ALREADY here on thirdgen.org if you just do your own work. You're literally doing NOTHING to help yourself. You want people to hold your hand at this point. You might as well post your address and ask someone to come do it for you.
You've answered your own question, you're not using the ECM anymore. so remove "sensors" then. This isn't rocket surgery.
I know all about these cars because I read, then I read some more. Then when I am done reading that, I go read more.
I already have dug in. I'm simply asking what the sensors are for so I know whether or not I can get rid of the wires leading to them. Not asking anyone to hold my hand....I've swapped my engine, rebuilt the top end, doing a full UMI suspension swap/upgrade, sub frame connectors, cutting out and welding in a new quarter panel section, adding a TCC lock up kit, added and am rewiring an electric fuel pump w/relay, etc....and did/doing it all by myself. But I know that having the answers to some questions I don't know will help prevent unneccesary mistakes. I guess that's alot to ask on this forum.
The only sensor you pointed to was the MAP sensor. You didn't show us any sensors on the engine, just pointed to a couple wires that you said connect to the engine block.
Obviously you'll want to have a coolant temp sensor and oil pressure sensor to operate the gages in the dash. I think the knock sensor is in a freeze plug location on the small block Chevy engine, so don't remove it unless you're ready for coolant to gush out of the engine block.
