I have and 84 camaro i'm trying to hook up the stock water temp gauge, does anyone know where the wires for the sending unit are, where they come out of the firewall, which side the stock sending unit is on a 84 Z28 H.O.?

 

The temp gauge sensor is in the driver side head, between the first two spark plugs. The wire is dark green and goes into the loom and towards the driver side and enters the cab through the C100 bulkhead connector (pin F5) and to the gauge.

Btw, the wire splits in two on the inside of the C100. One goes to the temp gauge, the other one to the ignition switch.

Hope this helps.
Lou

(click image for bigger size)

 

the bulkhead connector; is that under the relay farm? so if I run a wire from P5 to the sensor we should be good?

my sensor pigtail has 2 wires, is one for ground? I thought it grounded to the block. The car I got the pigtail off of had an aluminum intake.


P.S. thanx for the schematic but I already have that in my book although mines not colored

 

Yep, the C100 is in the corner by the brake booster, under the "relay farm" (that's quite fitting ).
You don't have a dark green wire in the engine harness? Look for F5 on the engine side of the C100 and trace it in the wire loom. Maybe somebody just cut it off or something.

Yes, you can connect the second wire to any good ground. Some sensors are grounded through their threads, some have an extra wire. Intake is never considered a good ground so GM usually puts two-prong sensors on it.

Lou

 

Is there a way to disconnect the harness from the engine side of the firewall?

 

.......B.U.M.P.

 

Yes.
IIRC, there is a bolt through the connector so you'll need to undo it first (possibly 8mm). Then just pry and pull on the connector and it will eventually come off, depending on how much tar (yes, tar) somebody used to seal it.

Hope this helps.
Lou