What is this Green Wire

KBabcock

True Classic
I was working under the car replacing the coolant lines by the engine and noticed this unattached wire hanging down. I am getting ready to start work on the FI so the car has never started since I bought it and want to know what this wire by the oil filter goes to. It is a forest green wire similar in color to a wire to the starter with a brown plug cap. I could not see anything it would plug into. Can anyone send me in the right direction as to what it is? My car is a 85. Thanks in advance.

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Is your O2 sensor hooked up? The O2 wire similar and looks similar iirc. It usually goes around the other side of the engine, but things happen over time.

UPDATE: I went out to my 85X and looked at the connections. My guess is wrong, the O2 sensor has a male plug on the end of the wire. For the first time, I am wrong again. :(
 
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I was working under the car replacing the coolant lines by the engine and noticed this unattached wire hanging down. I am getting ready to start work on the FI so the car has never started since I bought it and want to know what this wire by the oil filter goes to. It is a forest green wire similar in color to a wire to the starter with a brown plug cap. I could not see anything it would plug into. Can anyone send me in the right direction as to what it is? My car is a 85. Thanks in advance.

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There is an oil pressure warning light sender in the block to the left of the crankcase breather. This wire should plug in to the sender there. Does your oil pressure warning light come on when you turn on the ignition before you start the car?
 
Here is a picture from my 86. Looking to the left of the dip stick: the green wire with cylindrical boot is the temp sensor connection, the black wire with the squarish brown connector is the thermo-time connection. I don't have a picture of the oil pressure connection handy.
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Ok, curiosity got me to go take a picture of the oil pressure sensor on my 86. Brown boot, but looks like a black wire. It is not in a great location for a quick photo. The connector is just above the small red wire in the center of this photo.

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Here is a picture from my 86. Looking to the left of the dip stick: the green wire with cylindrical boot is the temp sensor connection, the black wire with the squarish brown connector is the thermo-time connection. I don't have a picture of the oil pressure connection handy.
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Boy that sure look like it and the location is spot on, I'm at the office today but will take a look as soon as I get home. Since the PO never got it running he wasn't sure what was and was not working when he rebuilt the engine. I've found a few wire he had not connected.
 
There is an oil pressure warning light sender in the block to the left of the crankcase breather. This wire should plug in to the sender there. Does your oil pressure warning light come on when you turn on the ignition before you start the car?
The oil pressure sensor wire is usually gray/yellow striped or gray/red striped.
 
The GRN/WHT wire color along with the brown boot suggests that it is for the sender for the coolant temperature gauge.
Boy that sure look like it and the location is spot on, I'm at the office today but will take a look as soon as I get home. Since the PO never got it running he wasn't sure what was and was not working when he rebuilt the engine. I've found a few wire he had not connected.
+1 Yep, just checked the wiring diagram, green w/white is the sending unit for the instrument panel temp gauge.

Just as an FYI, the coolant temp sensor for the FI system lives in the stat housing and has a typical Bosch FI square boot connector.
 
Nope that was not it, that green wire with the white strip is there already. I took a picture of it from the top and can now see this is actually a grey wire in a forest green sleeve. It passes through the fire wall to some place. You can see it on the left side of the picture, little out of focus.
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Nope that was not it, that green wire with the white strip is there already. I took a picture of it from the top and can now see this is actually a grey wire in a forest green sleeve. It passes through the fire wall to some place. You can see it on the left side of the picture, little out of focus.
Check the oil pressure sender then. It's above the starter in the block. See my crappy picture above. That could be a grey wire in my picture. You are running out of connections to check. :)

Here is a picture. At the center of the block, just below the head and right of the oil filter location.

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Thanks Jim!!!

That was it, the wire cover fits perfectly to that switch. I missed it over the weekend some how. If you every make it to Chicago I owe you a drink!

Thanks to everyone else as well. We will be talking again soon, I'm starting the gas draining this weekend to figure out what is wrong with the FI, so lots more fun to come.
 
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