Least used function or feature on our cars?

[Jonathan]

So... I was going through some boxes of parts and came across my "used crap" box. I saw an old defrost switch in there that could be made to work again if I can find the patience to put all the little pieces inside it that sprung loose back together. Found a used "full throttle" microswitch as well. It is the one "with the flap" that all cars have, even though my car has two of these microswitches due to it being an automatic.

I've replaced my full throttle microswitches before from getting seized up by dirt and grime or maybe just being tightened too much by way of the little securing screws. I was going to clean up the used one I have in an attempt to get it to work again before buying a replacement for the one without the flap.

Got me thinking about how useless both of these two things are.

Not 100% useless, but pretty close. In terms of how often they get used anyway. I do floor the accelerator once and a while though, so I'd consider my full throttle microswitches as more "useful" than my defrost switch. I can't remember a single time I've used the rear window defroster.

What else on the car would you consider the least used or most useless feature or function?

[MikeWard]

Lambda light
lambda.jpg

[DMCVegas]

I've used the Defroster Switch a few times. Driving through standing water when it splashes up on the exhaust manifolds will steam up the rear glass immediately. So the Defroster does indeed work, and is needed

Most useless feature? For me it's a tie between the Diagnostic Plug and the Air Valve Inlet.

[Bitsyncmaster]

Lambda light
lambda.jpg

In stock form, agree.

I drive the lambda light now with my wideband error code. It flashes when I first start up the car.

[Jonathan]

Lambda light, haha, nice one! The "can you count to 30,000 miles" feature. Assuming you have a functional speedo/odo that is, lol.

The air valve inlet/exhaust manifold stove is another good one... my car had just the duct tucked into the area of the exhaust manifolds but no actual stove bracket anywhere when I got it. A useless feature made more so by being an incomplete useless feature. Cold air inlet (performance) duct made all that go away.

With another automatic transmission fancy feature, the shift interlock button on the early style shifters is useless. For it's intended purpose anyway.

[Nicholas R]

In stock form, agree.

I drive the lambda light now with my wideband error code. It flashes when I first start up the car.

Similar; mine is wired up as the Check Engine/Malfunction Indicator light for the engine swap.

[Patrick C]

1.) Lambda Light
2.) Rear Defroster (in fact, DMCH has a supply of non-defrost rear windows that the factory was planning on switching over to. Even they knew the heated rear window was a useless feature)

[Horsebox]

I've replaced my full throttle microswitches before from getting seized up by dirt and grime or maybe just being tightened too much by way of the little securing screws. I was going to clean up the used one I have in an attempt to get it to work again before buying a replacement for the one without the flap.

It shouldn't take you too long to get it working again. I used a small jeweller's screwdriver to lever the long plunger out, then blasted the inside with contact cleaner. It's been fine ever since but they seem very sensitive to being overtightened but the fixing screws.

[Dangermouse]

1. Door buzzer
2. Chick magnet

[AugustneverEnds]

1. Rheostat
2. Lambda light
3. Ignition/Door Buzzer
4. Toll Booth Window