Sorry no pics, At least I think it's a sensor. It's in between cyl #6/8 on the passenger side. You can only see where it plugs in with a mirror because its under the manifold, and it's in to the head, not the manifold. Single wire connector. It broke off while I had a compression test done (at least I think it broke then). Thought it might be a coolant temp sensor of some sort but everyone says it's on the driver's side. I let the car idle for 15 mins and a short drive and my temp guage didn't move (I think it should have a bit). This is a bit of an issue because I'm facing a 550 km drive in 30+ celcius weather tomorrow, with hills. I just installed an air dam so it should be fine (had to use the heater to cool the car when I drove to where I am.)

 

It's the fan switch for the secondary fan(sensor-like, yes). But no worries about it affecting the way your car will operate--unless, of course, the engine heats up to 240* when that fan is supposed to come on.

Depending on how much of the end broke off, usually you can still stick the probe end of the connector into it, and it'll stay in and work until you get around to changing it.

 

I don't have a 2nd fan so hopefully it doesn't actually do anything

 

If you have only a single large fan then this is the temp sensor that turns the fan on. There should be a dark green wire that goes to it, from the fan relay on the driver's side bulkhead.

 

Your car is an '89 TPI, and it's only got one fan? Does the fan work now or has it ever, that you know of? If so, do you know at what temp it turns on? Does it turn on when you operate the a/c? Sorry for all the questions, but part of your set-up apparently isn't original. So to get an idea of whether or not that switch is operating anything and when, we'd need to know what set-up was original. But to try to cover all the bases:

If the engine is original and the fan was swapped from dual to single, then your fan might be wired to operate like the primary fan of the original dual fan set-up--for ECM operation with the coolant temp sensor in the front of the intake manifold. And in that case, the fan switch in the head prolly isn't operating anything, although it's prolly still wired through the a/c pressure switch to kick the fan on when you turn on the a/c.

If the single fan is original and the engine was swapped, then as said, that switch would be the main control for your fan, and you definitely need it connected.

But it's also possible that whoever did the TPI swap connected the original single fan to operate like the primary fan of the TPI dual fan set-up in my first-case scenario above, with the ECM and coolant temp sensor. So if the fan works now while the switch isn't connected(and with the a/c off), then this would look like how it's connected.

Clear as mud?

 

Most likely his car only had one fan from the factory, like mine.

 

Your '84 car and the early TPIs from '85 and '86, yeah, but your '88, a TPI, and his '89 TPI with only one fan from the factory?

I see you're both in Canada, so possibly an export thing? Non-a/c maybe? Curious, is it operated by the ECM like TPI cars or by the fan switch like TBI cars?

 

My 84 doesn't have an electric fan at all, never did. The 88 has a single fan due to the lack of A/C. I don't know offhand whether it's controlled by a switch or the ECM. The fan works just fine so I haven't had enough incentive to look into it.