What plug am I missing?

[cfleury14]

Hello all,

I have an '85 coupe. I was topping off the oil yesterday and noticed that there is a place where it looks like an electrical plug should go, but there is no wire or plug to go there. I have looked at multiple pictures and diagrams and cannot figure out what goes there. Pictures below. Anybody have any idea what goes there? Is it critical?

As always, thank you all in advance!

Chris

[proporsche]

Not to worry too much it is only for factory testing-diagnostics plug connection..
Ivan

[rwest]

Others will verify, but I believe that is a test port, so not used unless a tester is plugged in.

[FrankM_]

Indeed the test port for the factory. There should be a black cap covering it. It was missing on mine too.

Pretty useless port, I believe one of the pins gives you an electrical pulse for TDC.
I have the DME test manual (for field service) and that even doesn’t mention this port, so it was a factory only thing.

Frank


Sent from my iPhone using Tapatalk

[kees]

Here is a picture with and without the black rubber cover...





Kees

[GH85Carrera]

What is the part number for that rubber plug? Is it even available now?

My car is a long way from a concours winner, but I like it to have all the original parts, or improved parts. Over the years I have had a few people ask about that plug when looking at the engine. Most of them look at me like I am making it up when I told them it was a factory only test plug, and had no purpose at all after the day the engine went down the assembly line.

A black plug would make it harder to see, and fewer questions about it. I have though about just removing it. In the end, it is a really minor thing.

I am just amazed that Porsche spent even one dollar, or Deutsche Mark, to put it on the engine, and use it only once.