Does anybody know what this is? It has a wire that goes nowhere. All of my gauges work.

That's the gauge oil temp sender. What do you have your oil temp gauge connected to?

The one above it looks like a gauge sender. I think that's an idiot light sender. See if the wire is grounded with the engine off, and not when the engine is running.

Don't know. All I know is that before I got the motor rebuilt the pressure gauge worked but the temp didn't. I asked him to fix it and now I have pressure and temp.

The "can" sender above the unknown sender is the oil pressure sender. The "unknown" sender is the oil TEMPERTURE sender. The oil pressure switch is back by the thermostat. There's a second oil temperature sender on the other cam cover, but I *think* it's actually a thermo-time switch for the cold start system (which you obviously no longer have). I suppose it's possible someone threaded a gauge oil temp sender in the hole for the TTS, not realizing there was one already on the engine.

This is all I have to show you. The first one is mounted at the front of the motor and the second one is at the rear. Both are on the horizontal plane of the motor and look similar.

Front then rear

Exactly as I said. The big can thing visible in the top photo is the oil pressure sender. The sender at the rear of the engine, by the thermostat and the oil breather, is the oil pressure switch (controls the light). The oil temp sender is the one you marked "what is this" in the first photo, below and forward the can sender. On the other cam cover (passenger side), pointing forward, is yet another sender hole, which will either be plugged, or it has a thermo-time switch in it (what came stock), or it has an oil temp sender someone else stuck in later.

Buy yourself a copy of Wayne Dempsey's 911 rebuild book. It covers this pretty well.

I have one....

I feel like

Everything is hooked up and working so what an I ti do?

I believe you.

In your pic it shows a (blue?) wire going to the pressure sensor, and a second wire(green?) presumably going to the sender that you are asking about. That wire is running your temp gauge.

Each sender has only one wire. The ground is provided by the engine case.

That green wire you see next to the blue one is plugged into the sensor on the motor but doesn't go anywhere.

Allan, Probably when you had the engine rebuilt the mechanic added a temp sender (the correct one for your gauge even) where the thermo-time-switch is normally located. Your red boxed area is the original oil temp sender unit from a stock 2.7. If your mechanic got the temp gauge working and that wire no longer goes anywhere, I say pull the wire, it's no longer needed.

Dang, my edited picture sucks, my red circled area says "Thermo-Time-Switch" on the left side. That is where I figure your mechanic added a good/working temp sender.

I do have a sensor there as well but it doesn't have a wire on it either...

You may just have to trace out your oil temp wire to find where your mechanic is getting the oil temp signal.

It isn't typical, whatever they did, as the sensor in question is indeed the engine oil temp sensor and should land on the back of the gauge. Perhaps your mechanic has the temp sensor remotely located?

Yeah, that is a little wierd. The gauge works, so he must be getting the signal from somwhere?

Thanks for the help guys. You were all right.

Drove the car to my office and noticed that I had no oil temp.

Got to digging around and found a mysterious wire with a male connector on it.

Plugged the green wire from the temp sender into it and guess what?

210 degrees.

I'm glad the you got that worked out.

I'm also glad that another 74 914 has joined the ranks of 914-6.

Who was it that said in the future we will all have sixes? I think he was right.