EASY! My grandmas '03 Camry 4-cyl. Oh my god! It is horrible! Uncomfortable, ugly, slow, too common, and most of all, a Toyota! She loves it, it'* perfect for what she needs it for, and that'*, well, driving like a grandma. I floored it one time, you know, the good 'ole "Italian tuneup" , and I think my brothers '93 Taurus is faster.

An Opel GT! They looked cool, but what a POS they were to drive!

I once had to drive a rental Jeep Liberty, the latest gen. It was a rolling brick with no brakes. Also had a terrible center of gravity and felt like it would tip over everytime I turned it. Second worse? A Dodge Caliber. No shifts at all, and its acceleration was anemic.

My Mom'* Green on Green on Green on Green 97 Expedition. It is not only ugly, with its green roof mounted sun visor, and bug deflector, but its *-l-o-w too. You would think the 5.4 wouldn't be bad, it has the wrong gearing to be fast and it'* limited to 99
and did I mention the Green cloth interior with green plastic on the dash?

I would say either the 2004 Hyundai Accent from the driving school I learned on, or a 2011 Regal. The Buick felt like it was gutless, and was kind of disappointing..

This is a little hard, but I'll say my 1980 Bonneville. Very slow, I think 0-60 was about 20 seconds. Infamous, Olds. 350 diesel and TH200. A lot of wiring on a motor that supposedly didn't need them. Also years ago when I moved from my apartment to my house, I was driving the car and noticed the power steering was gone. No problem, right. I drove 12 miles without stopping and when it came time to slow down a little. I had no power brakes and took 2 blocks to stop the car. That'* when I learned of hydro-boost.

Dodge Aries (K-car) my friend had was the biggest piece of junk I've seen.

Opal sucked a$$! but Dodge Dart was a true POS

Worst car I ever owned was a '55 Morris Minor, the original 803cc engine had been repolaced by a later 1098cc motor with 43 thundering bhp that would get it up almost 70 mph on a good day, Desperately uncomfortable, the view from the divided windshield was like peering out of a letterbox, noisy as a cat fight, the brakes didn't even match the tugboat performance, no could it go round corners, tiny trunk as well.
Worst American car was a '79 Chevy Monza, asthmatic performance (iron duke 151) , uncomfortable, leaked everywhere, for went wrong with this car than I can remember, the stick transmission had an unpleasant habit of engaging 2 gears at once. I was given it but still felt ripped off!.
Roger.

Every Monza made was a POS Roger. Including the Monza trim level of the Corvair, Hard to believe this was the original "Concept" for the Monza back in '62. The name seems to have carried a curse with it.

Kia minivan 98 and a 2011 ford f250.. The Ford is a farm truck with no balls I hate that truck and somehow I always manage to be the one driving it when im out here on the farm 0-60 in like 15 secs