Thunking on steering wheel at speed with no steering input

Boy this will get long so I'll try to make it short and silly I'm having a similar problem on the silver $700 car that's been on the road now for about 2 years that we own bought in Raleigh North Carolina the lady we bought it from was told that needed $8,000 worth of work this was not one of the things. This car has a steering problem similar to yours I've had the alignment checked I've had the car up in the air personally here and looked at all the front end components the steering yoke all of it everything is spot on if I disconnect the steering yoke inside of the car from the rack I can turn the steering assemblies without any clunking no noise alignment holes everything is perfectly spot-on in the tires wear perfectly evenly all the way around the car this is the way all of my generation twos are but I have this noise and the steering column and it's coming from above the yolk where it connects to the back of that electronic steering nonsense in the car right above my knees I know it is in that electronic mess that plugs into the big silver box sitting right behind your start button panel in front of you how it all works I'm not exactly sure it's just electronic assistive steering but not steer by wire. I have two power steering units out of an '09 and an '06 sitting on the floor right in front of me they're made by two different manufacturers but that will interchange and plug up this weekend or next weekend I'll get around to taking the unit out of the silver car and putting one of these other units sitting on the ground which work perfectly because they're both out of my cars and see what changes It should make the problem go away If you pick your wheels up off the ground. And turn the steering wheel from 12:00 to 3:00 and then from 3:00 very quickly over to 9:00 you will feel something in that steering mechanism that catches up from 3:00 to 9:00 and 9:00 back to 3:00 but it's hard to discern from 12:00 to 3:00 or 12:00 to 9:00 if that makes any sense you'll feel like this round gear making a circle and catching up with where you are in the steering process it's quite weird feeling It happens in none of my other three generation twos which are in exactly the same conditions that I promise you I can't even get the units that I have sitting on the ground if I hook a steering wheel or a hub to it and turn it and do the same thing I'm doing in the silver car at the different clock angles this units I have on the ground don't do this or I can't feel it in my hand so I'm pretty sure the steering unit on this car is some kind of fubar. I don't know what's wrong with it and I don't care but it doesn't feel right speed doesn't matter I can go 80 mph in the car it's still steers the same but the clunkiness is still there It's not necessarily unnerving it just it's kind of uncomfortable if that makes sense And if I was driving this car everyday I would have already ripped this out and fixed it I have three other cars that I drive in rotation to keep them all charged and driving and healthy and all that so this is the fourth car and I don't drive it very often My ex was using it before she died for Amazon flex and all of that and funny thing is she didn't even notice it but she is one of those types

 

I would inspect the bolts that secure the steering shaft to the steering column and the steering rack. Could be some looseness there and tire balance vibration is causing the steering assist motor to "chatter".

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Wen you make a correction to steering do it feels like something sticking until you move S wheel past the stick point?

 

Maybe the latch that holds the steering wheel height has worked loose a little and there is some funny vibration at speed that it resonates with? Our latch loosens up from time to time and I notice it as a slight clunk when just enough upward force is put on the steering wheel to lift the column up. The fix is to loosen that latch, and reapply it. Usually the steering column moves some during this operation, since it falls down when the latch is released.

Why does the latch loosen up? That is a more interesting question and I don't have an answer for it.