Designing a car is an immensely complicated business, full of potential disasters.
The fact that manufacturers normally get it right so much of the time is one of the wonders of our age. But they get it wrong sometimes, perhaps because they had a bad idea, or a good idea didn’t work out, or they were following a fashion which should have been thrown in the sea years before.
Here are some examples of design flaws, presented in alphabetical order of the cars they apply to. As a bonus, we'll round things off with a few flaws which have somehow been allowed to spread throughout the industry. Let's take a look:
Alfa Romeo MiTo: sidelight operation
Switching on a car's lights normally usually requires a single action, as it should. In the case of the Alfa MiTo (never sold in the US), the driver had to delve into the trip computer, making no fewer than seven button presses, and could do so only when the car was stationary. Switching them off again was a reverse of the same process.
In fairness to Alfa Romeo, the same craziness could also be found in several Fiats. Fiat had the good sense to abandon the system after a few years.
Audi TT Mk1: crashing
Everyone was wowed by the design of the original Audi TT when it was unveiled in 1998. The picture was clouded however when the cars hit the roads and reports came in of an unusual number of high-speed wrecks involving the model.
The company's response was to recall the car, revising the suspension, fitting a rear spoiler, and adding handling technology – and these changes resolved the problem.
Chevrolet Cobalt: ignition switch
Incredibly, the ignition switch in the first-generation Cobalt was designed in such a way that it could easily rotate inside the barrel without being turned by human hand. If this happened, the engine shut down and the power steering, braking assistance and airbags became inoperative, with appalling results.
General Motors reacted slowly to the problem, leading to enormous fines, congressional hearings and many court cases. This is known as a Cobalt issue because the Cobalt was a particular big seller, but it also applied to the related Chevrolet HHR, Pontiac Solstice, Saturn Ion and Saturn Sky. The issue affected nearly five million cars sold globally.
Chrysler PT Cabrio: rear access
The convertible version of the PT Cruiser was notable for its scuttle shake, which was once compared to that of the Morris Minor convertible. A less well-known feature was that the front seatbelts were positioned in such a way that they prevented easy access to the rear.
Anyone wishing to climb into the back had to push the belts down and climb over them or pull them up and scramble underneath. The only other option - putting one hand on the side of the body and vaulting in - was possible only when the roof was folded down.
Citroën C3 Pluriel: roof rails
Pluriel is the French word for 'plural'. Citroën used it to emphasise the fact that this C3 derivative could be configured in various body styles. One of these was a convertible. It could be achieved by removing the roof rails which extended from the top of the windscreen to just above the bootlid.
Unfortunately, there was no space to carry them anywhere else in the car, so you had to leave them at home. That was fine if you could guarantee good weather for the rest of the day. If you couldn't, there was a risk that the whole interior would become soaked. And this car came out in 2003, when weather forecasts were much less reliable than today, and even then much less accessible (no smartphones). The model was never sold in North America, which is probably just as well.
Citroën XM: parking brake
Citroën's largest model of its time was one of several cars fitted with the thankfully now unpopular feature of a foot-operated parking brake. The brake itself worked well, but became problematic during hill starts if the car had manual transmission. The driver's left leg was required to operate both the parking brake and the clutch pedal, which it obviously couldn't do at the same time.
To avoid rolling backwards (possibly into the car immediately behind), the driver had to devote their left leg to operating the clutch and use their right foot on the throttle and brake pedals simultaneously. To say the least, this wasn't easy.
Fiat 500 TwinAir: engine vibration
Fiat's wonderful little 875cc two-cylinder TwinAir engine added even more cuteness to the already almost impossibly cute 500. Its least attractive feature was a strong vibration, caused by the fact that the power strokes were relatively large and far apart in time compared with those of an engine with more cylinders.
After a few years, Fiat improved the situation considerably by fitting a dual-mass flywheel, which soaked up most of the vibration. This applied not only to the 500 but to other Fiats and Alfa Romeos fitted with the TwinAir.
Fiat Multipla: lack of crumple zone
We are speaking here of the original Multipla, based on the 600 produced between 1955 and 1969. The 600 was a tiny car, but Fiat managed to fit the Multipla variant with six seats by adding an extra row right at the front.
As an exercise in packaging, this was very impressive. However, it also meant that there was almost nothing between the driver and front passenger and anything they might encounter in a head-on accident. If EuroNCAP had been around at the time, it would have had stern words to say about this.
Fiat Panda 100HP: bouncy
This is not going to go down well with fans of the 100HP, who regard it as a brilliant little hot hatch. They make a good case, but others were put off immediately by its tendency to bounce from one bump to another. Fiat had uprated the suspension from standard spec, but seemed to have tested it only on very smooth roads.
If you didn't like the 100HP for this reason, it was easy to follow it up with criticism of the very high noise levels and the fact that the seating position best suited drivers with very long arms and short legs.
Ford Model Y: windshield wipers
For complicated reasons, the speed of the wipers in the first Ford developed specifically for European markets was related to conditions inside the engine. The more power you used, the slower they went. On rainy days climbing uphill, this was unhelpful.
In fairness, Ford reduced the price of the base model to just £100 (or about $8000 in today's money)in October 1935, which would not have been possible if the car had been fitted with a constant-speed electric wiper. However, as one reviewer wrote at the time, "More than once during heavy rain we had occasion to wish that this were a £101 Ford."
Lincoln MKC: switching off
The MKC crossover had one button to switch the engine on and off, and another to engage Sport mode. Nothing wrong with that, except that the first button was mounted on the dash directly below the second. Drivers who wanted to revel in the delights of Sport mode might accidentally cut the engine while the vehicle was moving, which would definitely be a bad thing.
Ford (of which Lincoln is the luxury brand) issued a recall to relocate the start/stop button. Fortunately, the original design flaw had nothing like the same consequences as the Chevrolet Cobalt ignition switch scandal.
Matra Rancho: side windows
Very early examples of the Rancho did not have catches on their sliding side windows, which created a spectacular security risk. As one reviewer colourfully put it (with some confidence, though without actually putting this to the test), "A child of four, holding a toffee apple in each hand, could break into the car in under five seconds."
Window catches were added to the car’s specification shortly afterwards.
Mazda RX-8: rear doors
The RX-8 was rightly praised for its excellent handling but criticised for its poor economy and lack of mid-range performance, all of them caused by its compact (just 1.3 liters) but thirsty rotary engine. Hardly anyone pointed out a design flaw which had nothing to do with the engine. The RX-8 had four doors, the front ones being hinged at the front and the rears at the rear.
The rears could not be opened unless the fronts were already open, and there were circumstances in which it would have been impossible to leave the car if you were sitting in the back.
Mercedes A-Class: Elk test fail
The first-generation A-Class had only just gone on sale in 1997 when Swedish magazine Teknikens Värld turned one rubber side up during what has become known as the elk test, a slalom actually designed to simulate avoidance of an unexpected moose.
The resulting publicity was among the worst Mercedes ever suffered. The company responded by adjusting the suspension (which was not well suited to a car with a high centre of gravity in an emergency situation) and fitting electronic stability control. These changes were applied not only to later examples of the A-Class, but also to the 17,000 which had already been sold as part of a recall.
Mini Clubman: rear door on the wrong side
The Clubman was devised as a larger, roomier version of the BMW-era MINI hatchback. The current model has four passenger doors, but the original had just three. The single rear door was called the Clubdoor, and it was on the right-hand side of the car - correct for left-hand drive markets like Germany and the US but not for, to take one example, the UK, where it was manufactured.
A left-mounted Clubdoor would have been possible only if MINI had gone to the trouble and expense of finding a new home for the fuel tank, which it declined to do.
Nissan Almera 2.2D: noise
One of the engines available in the second-generation Nissan Almera was a 2.2-liter turbo diesel. It was a decent performer, but that didn't make up for the fact that it was also incredibly noisy, both for occupants and nearby pedestrians.
Things weren't quite so bad at motorway speeds, when wind and road noise partly obscured the din. Otherwise, it was just unacceptable, even for a car launched as early as 2000.
Nissan Juke: roll centres
In a press statement about the first-generation Juke, Nissan claimed that its roll centre heights were "are as low as possible . . . to reduce body roll in corners". However, as a disappointingly small number of journalists pointed out, body roll in fact increases as the roll centres become lower.
This could have been interpreted as a misunderstanding on the part of the press office, but the Juke was indeed notable for its body roll. This was especially problematic in the case of the 190 hp 1.6-liter turbocharged DIG-T version, which was fast enough for the roll issue to cause awkwardness.
NSU Ro80: unreliability
The Ro80 was an attractive and innovative car with two major problems, both caused by its under-developed rotary engine. First, it was tremendously uneconomical, which became overtly tiresome during the 1973 fuel crisis when prices surged. Second, the tips of its rotors kept disintegrating, which rapidly led to complete engine failure.
The problem was fixed, but the car's reputation never recovered. Nor did NSU's. The Ro80 was therefore - and uniquely - a Car of the Year award winner (1968) which essentially killed the company that built it: battered by large warranty claims, it was forced into the arms of Volkswagen. The NSU name died in 1977.
Unless you can find a way of fitting it to the roof, mounting an engine behind the rear axle of a car is the best way to guarantee instability. It worked well enough for small cars with low power outputs, and to an extent it worked on early Porsches up to the original 911 introduced in 1964.
However, as outputs rose, notably with the addition of turbocharging, the 911 developed a reputation for wanting to swap ends. In fairness, Porsche has done a very good job of minimising the issue in recent years without making the 911 mid-engined, a development which would be heartily criticised by enthusiasts.
Proton Savvy: noisy reverse warning
One particularly unattractive feature of the Savvy supermini was its rear parking sensor, which gave out a piercing squawk when it decided that the car was coming too close to whatever was immediately behind it.
The same squawk was also emitted when the driver selected reverse gear. This usually happened twice in quick succession, because the shift into reverse was very awkward, and was unlikely to be completed successfully at the first attempt. As design flaws go, this was not particularly significant, but it would surely have been one of the easiest to fix.
Renault Avantime: awkward doors
The doors of the Avantime coupe - or SUV or whatever it was - were absolutely enormous and heavy. If they had been hinged normally, they would have been almost impossible to open in a car park without hitting the next car along.
Renault got around this by making them double-hinged. That was clever, but it also meant that they hardly opened at all. As a result, occupants had to walk almost to the back of the car, turn round when they reached the edge of the door and then walk forward again before climbing aboard. There must have been a better solution.
The Clio V6, powered by a mid-mounted 3.0-liter engine normally found under the bonnet of the Laguna, was adequately fast and very exciting to drive. A bit too exciting, in fact. Fitting a tall, heavy engine between the rear wheels of a short-wheelbase car is no way to achieve stability. Tales were soon told of enthusiastically driven early V6s flying off into the scenery.
The second-generation V6 was not noticeably better. Journalists attending the UK press launch of that car could go as fast as they liked along the straights of a test track, but were forbidden by Renault from driving it quickly round corners.
Volkswagen Golf R32: weight distribution
Both versions of the R32 had a heavy 3.2-liter V6 engine mounted almost entirely ahead of the front axle. The earlier model was quick in a straight line but difficult to manage round corners or over bumps.
Its successor was much better, at least on smooth roads. Over a sequence of closely-spaced crests, though, it was still very clumsy. Volkswagen removed its own design flaw by replacing the R32 with the Golf R, which had a much lighter turbocharged 2.0-liter engine. The R32's wonderful sound was a thing of the past, but the R was incomparably better to drive.
Let’s now take a look at some other general design flaws which are in many cases still widespread: