Triumph TR7, iron block, aluminum head, didn't have thread inserts or studs, just steel bolts into the aluminum head. Ended up putting in a lot of heli-coils. Wiring harness was some plastic strip that just broke in two.

1975 Fiat 128. The body came off the frame one day from rust and I sold it to a junkyard for $25. Good riddence.

French made Simca... junk. my first car at 14-15yrs old
Fiat X19... cute but junk. had to push start almost every day. popped a timing belt and bent 7 out of 8 valves. using shims to adjust valve clearance sucks!
having owned something over 200 cars (American Motors to Vw) since I was 15yrs old, I'm sure there were a few more, but it's all a blur now

'70s vintage Renault R-12...puke,metallic green...heli-coils aplenty...big farm boy, bigger wrench, aluminum head and block...head gasket repair lasted about 400 miles...almost as big a POS as the R-10 my Father drove for a while (although that was a rear engine car...LOL).

Hands down!!!! 1984 Citroen GSA!!!! Driving down the road the hood latch weld broke and the hood came up to say "Hey!". parachute cord. Next month a buddy was getting out of the back door, passenger side. Glad he had a hold on the door as the welds gave out and the door was held up by him. more parachute cord. Then the spark plugs started popping out. The threads had gone bad just from being driven? JB Weld. Then the oil pan cracked, just cracked. JB weld and weld the plug to the pan before adding new oil and filter. Filter attachment point stripped out. JB Weld. Driver's door welds getting weak, more JB Weld. Oh, and driving down a country road in Belgium the cv joints go out and the ball bearings fall to the road, no steering control. Sold it for equivilent of about $25.00 US. Bought in March 1987 for about $600.00 US, sold in July 1987 to a junk yard. Did I mention it was a 1984???

Second worse was an '83 BMW 318i. A real POS, but it couldn't compare to the Citroen. Oh, the second motor for the BMW only cost me $200 so that was not so bad...

1982 Pontiac J2000 The origional sunbird. It was actually my girlfriends car and I worked on it more that I worked on her. On the way back from our honneymoon I informed her that half of that pos was now mine and I was going to sell. I asked her which half she wanted to keep for herself. It went a week later.

Bugs, what crazy beasts! I love my '70, despite the loose steering and frequent dashboard fires. I can fix almost everything, and just haven't had time to tear apart and rewire all of the electrical. But when I do, that car is expected to move from "worst ever" to "almost Porsche-cool!"

Rick V made me redo my list...how soon we forget. The worst in this order:

1. 1982 Pontiac J2000 - a bill waiting to be paid...constantly! Kids would rather walk than drive it...at least they knew when they'd get where they were going.
2. 1996 Ford Windstar...so much wrong, so little time. $1500 later and the smog problem got fixed...got brakes more often than I got groceries. Electric problems...randomly the power locks would just start going on and off.
3. 1989 Suburban...bad rap, but I did go thru 3 transmissions before someone realized it was a bad core.
4. 1978 Toyota Celica...geez, plugged cat, blown head gasket, over heating, it goes on and on...

Worst?

It's a tie...

• A clapped-out Ford Pinto Hatchback. When it rained, it leaked water on me. Even though it had no sunroof, or t-top. Then again, I sold it for more than it I bought it for.
  
• A Datsun B-210. Very reliable, but embarrassingly slow and ugly. Especially when my friends had SS Chevelles, GTOs, and Road Runners...

1976 Rolls Royce LWB....Great Ride....just like sitting in your living room... if you live in BH's..... and it was like paying a BH's mortgage..you made monthly payments to the mechanic who worked on it....

1970 Dodge Challenger 440/6 Pack....Great until you hit 35 mph...then it launched itself like the Space Shuttle....whether you wanted to or not....and it rattled like the SS tooo...

1966 Corvette 427/425 HP......Fast and Smooth.....it would squat down and run like a horse with scalded balls....but what a thrill to watch the gas gauge move from right to left as we speak...

2000 Range Rover 4.6 HSE.

Enough said?

I didn't own it, but 9 years ago, after buying a Passat Turbo diesel to use in my work, the company informed me they were providing me with a company car. An Olds Acheiva. An hour after I picked it up, I was pulled to the side of the road, wedging my jacket behind the small of my back to ease the back-ache. A custom pad for my lower back stayed Velcroed to the seat for the duration, (and was passed on to a co-worker in the same situation when the POS was gone.)
It ate front brakes almost as badly as the late 90s Malibus. The A/C clutch seized one day on the highway causing a moment of panic before the belt snapped. It hated to go around corners and the "passive safety" seat belts were mounted to the door frame so they were held 4 inches from my chest.
I kept the Passat for family use through the next 8 years (3 company-supplied Venture vans after the Olds). It now has close to 370,000 Km on it and will likely be the last car I own (aside from the 'old E')
Les

Sorry to say, 1978 930...

Underengineered crankshaft thrust surface wasn't up to the stress from the new interlock that required the clutch pedal to be depressed when starting. Allowed 0.040" endplay to develop, requiring new crankshaft (don't a$k). Failed turbo seals laid down smokescreen worthy of HMS Hood in full getaway mode. Failed front caliper.... the list goes on.

Some of this might have been found in a PPI, but I had 15 minutes to decide 'go or no-go' and I picked wrong. In 13 months of ownership, repairs averaged $1K/month. Couldn't wait to get rid of it.

1981 Ford Escort. Spruce green exterior, mustard interior. Looked like a booger with wheels. Every time I washed it the rag turned green cause the paint was turning to powder. It stranded me everywhere I went. It left giant pools of antifreeze everywhere I went (waterpump, heater hoses, stopcock, another heater hose, in that order). Burned oil faster than my SC. When I took it in for smog check, they had to clear everybody out the garage because of the oil smoke. Both door restraints failed, so you'd better hope I didn't park next to you. Engine has 2 miles of thin hard plastic vacuum tubing that would shatter if you touched it. One day I started it and the smog pump locked up, that was interesting. It has been wrecked, so the driver seat was broken and it could not be aligned. Turn the wheel left during accell, right during braking to keep it between the lines.

1986 Renault LeCar

Bought it when I was 16 for $250. Absolutely unreliable, but I it was a hoot to drive, especially after I scored some performance parts from Archer racing. Cam, weber DCOE, headers... good for 100 hp at 7000 rpms. And it had the "big" engine... 1.4L.

As much fun as it was, it ALWAYS had something wrong with it. It was the only car I've ever owned that would overheat on the highway, or in January. Constant electrical problems, and needless to say parts were difficult to find, especially by the 1990's.

Ford Pinto - drove it all of 25 miles and had to abandon it on the side of the road. Blown head gasket. Paid $100 and then another $250 for the city to remove it from the highway and deliver to the crusher.

I see Rolls Royces going on eBay for less than the price of a mediocre 911 of the same year all day long. It never ceases to amaze me. I am often tempted to buy one just for kicks but I am afraid it would become "Static Driveway Art".

Mitsubishi Mighty Max?
My uncle has had one for about 12 years now for his work truck. Seems to be pretty reliable.

Let's see, I've only had one car, the 911, and it isn't bad so I'll just name a car that my family has had that has/is the worst: 1994 BMW 740i. Leaks oil. Tons of electrical problems. 'nuff said.

I had an 85 S-10 Blazer, that thing was built like a tank. Survived two head on collisions which should have killed it, and got over 450,000 miles on it before the cam lobes wore flat. Funny, my S-10 had the 2.8L V6 with a carburetor, not fuel injection.

I had... I believe an early 70's AMC Javelin.........it died a slow expensive death ......