4gr-fse doesn't make the list?

Olds quad Four

Nissan qr25de

 

The engine was solid, everything else around it sucked a$$, specialy the cooling system where the radiator was prone to rusting, which would then cause an overheat condition. This usually then resulted in head gasket failure, burning oil, etc, etc, etc.

 

Any Ford Pinto engine is garbage, and the Vega of course.
Though, the Mazda RX-8 rotary engine wasn't to reliable when it first came out.

 

Holden Starfire, a straight six that lost the front two cylinders becoming a 1.9L four that was more expensive to run than the original engine. Leaked oil worse than a british engine and ran hot in a hot country.

 

@ Mrraider. LOL Olds Quad 4, what a POS. It's so funny to me that American companies are still so far behind in OHC technology.

My Vote goes to 3 engines
1. Cadillac 4.1 L V-8 Pinged with under 100 miles on them, running premium fuel. Made a whopping 125 Hp, or somewhere thereabouts.
2. Mazda/Ford 2.0L 4-Cyl and 2.5L 6- Cyl from Probe's / 626. I have seen more head gaskets replaced on this motor than all others I've ever worked on combined.

 

I do recall the GM diesel car engines from the 80s being quite poor, but for some reason my recollection of the worst engine ever made was little .9 litre engines in Yugo's in the mid 80s. I even remember seeing reports of a measurable amount of them failing at 21K miles or less.

 

Overheat a Vega powerplant (especially the early-production ones) and it (could?) be done a lot sooner than that.

Temperature-control in the 140-cubic-inch Vega four was critical. The iron cylinder-sleeves inside the block expanded/contracted with engine-heat at a different rate than the aluminum in the block itself. Get it too hot it once or twice and you had a classic case of block-warping, with the engine usually good for little else than scrap-metal. Then, if the engine did last for any reason, the body didn't.....rust-holes would get it, especially with road salt.

 

The early 2.3 Liter aluminum block engines has NO cylinder liners at all, combine that with frequent coolant loss and you ended up with a cooked engine. Many failed with a massive hole in the side of the block. GM did this to save money. Oh and the valve seals were terrible even when knew, so the engine often ran out of oil.