one wire i just cant work out what its for

[ozbowhunter]

I have a couple of pics of a wire I cant find what its for the first shows the connector block it comes out of the other is the end anyone got an idea it is light green in color





and as you can see i have a patch to fix in the top of the fire wall never ends does it lol

[frog210]

Horn, Temperature sensor maybe...

[Dead Parrot]

Quick guess based on location, either for the fast idle AC solenoid or choke heat power.

[slam59]

I have one almost identical but black coming from firewall on mine and was wondering too about mine.
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[geezer#99]

Wiring diagrams! Search to your hearts content! Might have to blow them up a bit.
http://forum.73-87chevytrucks.com/sm...?topic=11766.0

[ozbowhunter]

I was thinking something to do with the ac where is the fast idle solenoid ?

[ozbowhunter]

ok had another look at all of this and the two wires coming out of the block are the dark green which runs to the AC compressor the light green which is the one I an trying to sort
I cannot find a connection for it any where the ac compressor has the dark green and an earth wire so im assuming this light green is the switch wire but to where it connects im lost will study the diagrams but if anyone has an idea please let me know

[ozbowhunter]

just went through the diagrams and there's no ac wiring listed man this is getting annoying lol

[geezer#99]

Dark green to a/c switch at the compressor. Light green to high idle solenoid on the carb. Like on my carb.

[y5mgisi]

Yep A/C related, and as geezer said, that one likely goes to the high idle solenoid as he has pictured.

[ozbowhunter]

thankyou
if mine does not have that solenoid as it has had the engine swapped before I got it is it something I can add ?

[geezer#99]

You sure can! Look on evilbay maybe. Or auto parts store or junkyard (aka experienced parts) emporiums.

[ozbowhunter]

is this a ground contact switch? if so can I check the system by making contact with the engine ground ?

[ozbowhunter]

am I right in thinking that without this solenoid the system wont work ? as in that the compressor clutch wont click on with out this contact

[hatzie]

Originally Posted by ozbowhunter

am I right in thinking that without this solenoid the system wont work ? as in that the compressor clutch wont click on with out this contact

Nope. It'll work just fine. The AC throttle solenoid kicks up the idle so the engine doesn't stall at every light with the AC switched on.

You can find GM wiring diagrams for your rig in my signature.

[ozbowhunter]

thanks
now im stumped the system wont kick on at all the compressor clutch wont click on when the switch is moved to aircon any ideas where to start looking ?

[Willowrun]

There is a low pressure sensor for the AC on the passenger side AC plumbing that has two wires that run to the AC pump. Unplug the connector going in to the sensor and when the engine is running and the AC in the on position take a paperclip or something similar and jumper the two posts of the connector that was plugged into the low pressure sensor. If your AC clutch engages you know that your clutch works but either your system has leaked its charge or you have a bad low pressure sensor. That is the first thing i usually do when a clutch doesn't engage and it is typically because of a non-charged system.....a leak somewhere.
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[ozbowhunter]

thanks I think I will be able to get in and sort it if there is a leak what's the best fix ?
is there a sealer for the system ? thank for all your help