78 SC Black engine plug - where did it go?

[GaryR]

This plug is located over by the throttle linkage. The WUR's plug is grey and plugged in, the CSV plug is blue-green and plugged in, where does the black one go? I'm thinking it was to the heater/blower (which is long gone) but would like to know for sure..




Thanks!

[blucille]

nope. heater blower is connected by larger spade connectors.

[Norm Faustino]

Wire color? try and look for it in the wiring diagrams.

[GaryR]

Originally Posted by Norm Faustino

Wire color? try and look for it in the wiring diagrams.

I'll look tonight, I think I can see the actual wires where they enter the harness down under the CIS.

Could be for my nitrous but I only install that during racing season..

[timmy2]

Safety switch for fuel pump on back of air plate for throttle body, or if it reaches, it goes to the AAR.

[blucille]

I've got three that sound about right, a blue, a grey and a black.

the black goes to the WUR on mine (79 SC)

blue to the CSV, grey to the baseplate of the air flapper

yup, it's a mess in there, ordered the parts for the trinity of oil leaks, and found a broken housing for the CSV, pelican box just landed on my porch! yipee.

[GaryR]

Thanks Sonnett, I believe the plug and receiver are color coded so they can't be mixed up. I'll carb-clean and double check tonight but i'm pretty sure on my 78 the CSV is blue, WUR is Grey, so I have to look at the baseplate to see if that's the one i'm mising. Car starts and runs fine but with engine out it's time to fix some little things like this..

[DaddyGlenn]

I just pulled the wiring harness off my '78 and if I remember correctly, I had three black plugs like that. One attached to the distributor "green wire", one to the WUR and the last to the AAR.

But the wire color will be a big help.

[timmy2]

There are 4 of those connectors on a '78. WUR, CSV, Air Plate Switch, and AAR. The green wire is a male plug.

[DaddyGlenn]

The AAR is the auxiliary air regulator. If you are standing at the back of the car looking at the engine it would be on the right side under the intake runners.

Is your '78 a US car or RoW? Mine is a ROW and did not originally have an AAR.

The PO added one and disconnected the throttle lock.

[timmy2]

Interesting DaddyGlenn, my '78 ROW has an AAR from the factory.

[GaryR]

From another post, this looks like where this black plug may go..

[DaddyGlenn]

Originally Posted by timmy2

Interesting DaddyGlenn, my '78 ROW has an AAR from the factory.

I know! Strange! My VIN shows my car to be an early production (#274) so perhaps the AAR was added later in the run.

Yes, Gary, that is the AAR.

[GaryR]

Originally Posted by DaddyGlenn

I know! Strange! My VIN shows my car to be an early production (#274) so perhaps the AAR was added later in the run.

Yes, Gary, that is the AAR.

Thanks for the help guys. As the wire got routed over to the throttle side I concentrated my search over there. I'm 99% sure I just need to pull it through to the AAR side and plug her in, done. I'll take a picture of each plug after I clean them up to have for future reference. What effect would having this unplugged have, apparently ran it all last season like that!

[blucille]

none.

the AAR primarily boosts the idle when the AC is turned on, not sure if it does much any other time

[GaryR]

My AC has most likely been molded into a Toyota wheel by now...

[timmy2]

AAR provides extra air on start up for high idle when car is cold. Closes after about 5 minutes and idle goes down.

[DaddyGlenn]

Originally Posted by timmy2

AAR provides extra air on start up for high idle when car is cold. Closes after about 5 minutes and idle goes down.

The plug provides the power to heat the AAR and close the valve that lets in additional air. Assuming your CIS was tuned without the AAR operating, plugging it in will cause the engine to run richer once it is warmed up. You will likely need to re-tune the CIS.

[jeffs9146]

On my 83sc the only black one I have goes on the Frequency Valve!

[GaryR]

I have a frequency valve? Does that tell me how often I visit a track?