First post. 90 TT. Car is running perfectly. Manual, 49k miles. Don’t punch me but it has an aftermarket ecu but I’ve never peeled up the passenger floor to look at it. It boosts over 14 psi when the ambient temp is cool and the air is dry. Boosts to like 10 psi when over 80 F and humid. All else is stock that I know of.

I was changing headlight bulbs when I noticed on the passenger side (LHD) an empty, dirty, corroded female wire connector. Looks like it’s been disconnected since before I got the car 11 years ago. The male was tucked up and out of sight so I tugged it into view for a pic.

I am just curious about what this is and why it has been disconnected. Any ideas would be awesome (maybe other than “some dude was lazy” lol). I can’t read wiring diagrams and I can’t tell if this is maybe an engine ground thing or an air temp sensor or what (I’ve been looking at uninstalled harnesses and simplified diagrams).

I want to clean up the connectors and plug it in for some reason. Again, the car is running fine (MAYBE the big *** loud cooling fan runs more than it should (it seems to kick on at lower ambient temps than my 94 TT from years ago…a different post maybe) but it’s bothering me.

Previous owner is the original owner and he passed away many years ago and there’s paperwork and receipts but nothing related to the ecu which I think has something to do with this but idk so I’m asking you.

I will try to attach a pic. What is this and should I plug it in or just leave it like it was, just sort of tucked away (no tape, nothing)?

thanks.



Unconnected wire behind and below (LHD) passenger side headlight housing - sorry: it was hard jamming my iPhone in that space SO I believe this is three different angles