So this weekend, I’m driving along the NYS Thruway using my rental car’s cruise control. Cruise control is set at 65 mph, and I am driving in the right lane.
Much to my annoyance, some yahoo creeps up behind me, and tailgates for quite a bit of time. There was very little traffic, so I am ticked off that this car isn’t simply passing my car. I am still going 65 mph.
Finally, the car moves into the left lane, and passes me. Then, that car moves back into the right lane, in front of my car. And then slows down to about 62 mph, forcing me, of course, to slow down as well.
Naturally, this sort of thing toasts my buns like nothing else. Idiot drivers! I knew I was maintaining a constant speed, because I had cruise control on. Then I realized I have no idea how cruise control works. With cruise control, am I actually going 65 mph at all times, or is the 65 mph an average speed that takes some fluctuations into account?
Some cars have a very aggressive cruise control; I’ve had a couple that would actually floor the accelerator on a hill in an attempt to maintain speed. On the other hand, I’ve driven several that will only accelerate a certain amount.
On a flat straightaway it’s pretty likely that you’re going to maintain the speed pretty accurately. There is no averaging going on; the CC senses when the vehicle’s speed drops below the set speed, and takes approprate action.
Now, this is with traditional cruise control that typically use a magnet attached to the driveshaft or speedometer cable and a sensor (induction loop), attached to a circuit that counts the number of times in a given period that the magnet goes past the sensor. It’s conceivable that newer cars with digital dashboards actually read the speed from the speedometer circuitry and then use that for the CC. But all the vehicles I’ve had do it the other way - the CC doesn’t even know how fast the car is going; just that the number of RPMs the sensor is picking up is lower than what it was set at.
Cruise control does take some fluctuations, if you start go up hill you will slow down a little usualy 2 or 3 MPH till the cruse controll downshifts and accelerates you back up to set speed. But it should be as accurate as the speedometer.
The guy who passed you and slowed down was an asshole who felt that you should have gotten out oh his way (how dare you not recognise he’s greatness) and wanted to punnish you so as to teach you a lession not to mess with him again. :wally
The best thing to do is just tap the brakes or hit coast and slow down a bit then reset the cruise controll at a safe distance untill he get tired and goes his self absorbed way then accelerate back to your cruiseing speed. Don’t get mad at him because one day he’ll try this or something worse to an asshole bigger than himself and we will hear about another road rage shooting on our highways.