Indy Rev

What is this port?


Its connected to this.



What are these green wires, and should they be connected?



Thanks

jeff spahn

The first one is an old test port. Ignore it.

The second is your CPS (crank position sensor), don't ignore that one.

The third is YGIAGAM (your guess . . . . )

snoz

I believe the second picture is the sensor for the test port, and the CPS isn't visible in the second pic.

Indy Rev

The first pic and the second pic are connected by a single wire.

jeff spahn

Pic one: End of FPS
Pic Two: The thing with the red arrow pointing to it that looks like a teardrop is your FSS. CPS is right in front of that on engine block under the line with the red paint on it. My Bad.
Pic Three:
No idea where these go. Perhaps to something that was an option on your car that has been removed?

jeff spahn

Oh, sorry. That's the flywheel speed sensor.

Indy Rev

Should this be connected to something or is it just a test port?

jeff spahn

IIRC it was discontinued after 1988 and isn't used any longer. I wouldn't worry about it. Thought they used it with emissions testing along with a sniffer port that might be to the right of it with a blue rubber cap. My 1990 S4 doesn't even have this sensor.

davek9

^^^ correct ^^^ that "test" port and the FW sensor pick up it's connect to is not used by any current test equipment and can be completely removed.

The Green wire(s) with the white Molex connectors (should be two pair)...

One is for when only Low-Octane Fuel is available located on the EZF connector (will remove 3 degrees of timing advance at WOT, if connected) Same circuit as the Temp1, it does the same when air box temp get too hot.

The other located on the LH connector will add more Fuel at WOT.

Most are hidden under black tape wrapped up near the connections.

The S4's don't need/have them as they have Knock sensors and will Automagicaly manage the spark advance if all the sensors are working.

PS: change those fuel lines!

Dave

Indy Rev

Thanks. Noted on the fuel lines