I was watching Easy Target, and Mac of course just yanks a few wires down, taps them together and the car starts. It's also funny how the hotwiring scene looked so "faked" or "unlikely", but I think this is one of those things where it really would have been that easy and they just for the sake of legal purposes depicted it being done in a way that would not really work (or be easy).
A few months ago I was helping my friend troubleshoot a problem with his 99 truck not starting, and I figured out how to narrow it down by shorting across two terminals on a part under the hood. It made the engine crank- and start- and drive off! Turns out, the truck was in reverse when he turned it off, and as a safety lock out they set it up so the car won't start unless it's in park. Well what I did forced the car to start by sending power straight to the starter. Since it was in reverse, it started driving backwards, so I had to run and catch up, hop in and put it in park.
My point is, before the steering column lock that requires the key being turned to be able to steer the car, that is all it would have taken to have a car going down the road! If you can pop the hood on an old car, you can drive it. But now there's all sorts of safeties built in etc. etc. so even his 1999 I was surprised allowed me to do that. But back around the time of MacGyver when he had to commandeer a few vehicles like the Camaro, truck, little cars in europe, haha, all of that would have been very possible, and I am not exaggerating when I say you could be gone in 60 seconds. If you are familiar enough with cars you look under the hood and can identify any part, you can locate it within seconds. The placement varies, but the design themes are pretty consistent across makes and models.
Again, I feel like I was born 20 years too late, *sigh*. As I broke down and got my hair cut today, I realized the 80's will never return
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"It's a real ugly thing to see in a dog. It's even worse in a human being." --The Golden Triangle
"I'd like a 16-inch pizza, run it through the garden, hold the chovies." -- The Eraser