I have several contenders for such a title,most were problems unique to the one car driven/owned.Just a few of them that stand out: Once had to rent a car,about 1989.Got a Plymouth Reliant,maybe an'88? Horn would blow -by itself- when wheel turned sharp to left.Also the radio only picked up two stations,and neither one I liked!!! Was glad when those 3 days were up!! Drove a 1995 (one year old at time) Kia Sephia once at work,I put it gear...and the shifter came off in my hand!!! Scariest one: 1977 Firebird.Trade-In car from a "push,pull & drag sale" at a local dealer. I worked for a wholesaler at the time,they had me drive it back to our shop to auction it.Wondered why I was getting a headache?? Pulled over,started looking at this car..."Northern" car,all rusted out underneath...with cut down pipes...with the windows up,it was like a gas chamber!! Drove it in the rest of way with windows down,on a cold,wet evening! Once owned a beat up '63 Chevy that sometimes liked to open it's right front door making a hard left....guaranteed to REALLY get the attention of your R.F. seat passenger!! (You had to slam it HARD or it would do this) Had a '69(German)Ford 17m that sometimes didn't like getting out of reverse,you had to crawl under it when it did this and 'jiggle' the linkages with a long screwdriver...once almost ran myself over??(Brake wasn't set 'all the way',car rolled a bit) Had a '71 Pontiac that you'd swear was possessed by all the electrical problems it had?? You'd fix one,another one shows up?? Eventually it burned itself up inside,(dash,front half of the interior)I never really did figure out just what touched it off,though I did 'almost' get it out...but too late.(Might add a few more later on...like that damned '90 Beretta...the service department's nightmare!!)