5 Of The Most Frustrating Engine Layouts Ever Designed

Cars used to be really simple. They would have an engine up-front, perfectly visible and surrounded by heaps of open space under the hood, a few seats in the middle, and a trunk at the back. As the years have progressed, though, the car has gotten immensely complicated, and while that brings many benefits, it also brings a smattering of negatives.

Bigger engines, more ancillaries, larger crumple zones, and heaps of plastic panels covering anything mechanical has meant that engine bays have become increasingly harder to work on. No longer can you just reach in with a socket and begin working away, which has meant working on your own car has become noticeably harder over the years.

I’ve always taken pride in tinkering away on my own cars — whether I’m doing them any good or not is another matter — but I learn along the way, and it’s quite enjoyable too, usually. That being said, when it comes to newer cars, I simply don’t bother any more. Having worked on some pretty complex cars and bitten off way more than I can chew a few too many times, I’ve learnt to leave it up to the experts on modern machines.

Not all cars are bad though, some are renowned for being horrendous to work on, and the mere mention of one such model will likely have your mechanic groaning before the job has even started. So, if you’re looking for something easy to work on, avoid these five cars, as their engine layouts make some of the most basic tasks an absolute nightmare to carry out.

Audi’s baby supercar bridged the gap between sports and supercars, and finally gave deep-pocketed car enthusiasts a real daily driver alternative to the Porsche 911. Sure, they could also shop at Chevy dealerships for a Corvette, but the fit and finish of contemporary ‘Vettes just wasn’t in the same league as either of these German bruisers.

When it came time to crack on with maintenance, though, R8 owners might have wished they’d walked into a Porsche or Chevy dealer though, as the four-ringed model is notoriously tricky to work on. Being mid-engine, the Audi’s 4.2-liter V8 sits directly behind the cabin, and access is far from ideal back there.

In order for everything to be both neatly packaged and still be presentable under the glass engine cover, certain ancillaries had to be buried beneath the naturally aspirated mill. For example, the air conditioning compressor. Unfortunately, the engine temperatures down there are a little much for the compressor to handle, and so it’s a frequent failure point for the R8. Replacement of the faulty part requires the engine to be removed, which itself means the back end of Audi’s flagship supercar to be pulled apart. Enthusiasts also point out that simple jobs, such as bleeding the brakes, are far more complex than you’d first imagine, which means — while the R8 is certainly more approachable than other more exotic supercars — maintenance is still a considerable barrier to enjoyment.

There is some good news, though — V10-powered models don’t require the engine to be removed for this job, so perhaps for once the sensible choice is to splash out and buy the Lamborghini-engine supercar instead?

This one is a particular sore talking point for me, as our family car is a facelifted S4, and while it’s an absolute joy to drive, getting anything done is a real pain. For starters, the supercharged V6 can actually be quite durable — there are many out there with north of 200,000 miles, and many of these are tuned cars with north of 450 horsepower too, but the maintenance required to keep them on the road in fine fettle can be a little intense.

See, Audi decided to locate many of the S4’s weaknesses underneath the supercharger, nestled within the ‘vee’ of the engine. Here, you’ll find the PCV, waterpump, thermostat, and supercharger intercooler cores — all of which fail frequently and leak coolant. Not that you’ll see it, as the coolant just evaporates in the heat of the vee.

To replace them then, it’s supercharger off, which in itself can be a pretty daunting and tricky job, as beneath the supercharger are a smattering of brittle plastic hoses, which love to crack as you remove them for access. That’s not the worst of it, though; the S4’s V6 is driven by a timing chain, or more specifically, four timing chains. They’re all located at the bulkhead end, too, which means it’s engine out time should you need to get the job done (which you will at some point). Expect to pay north of $5,000 at a reputable independent garage.

Equally tricky to access are the catalytic converters. There are two, and they sit right behind the engine – nigh-on impossible to access without removal of the engine. These are another common weakness too, meaning S4 ownership requires an awful lot of engine-out time. Certainly, it does in my case.

You might expect that something as exotic as an older Ferrari will be a bit tricky to work on, and you’d be absolutely correct in thinking so. The Ferrari 355 isn’t the only model that requires the engine to be removed for a cambelt change, but it is the last, so it’s worth singling out.

Naturally, sporting a Prancing Horse on the front means such a job won’t be cheap. Some enthusiasts claim the job can be carried out for around $2,000 — provided the mechanics don’t come across anything else wrong while they’re in there — whereas other sources suggest the bill could easily run north of $7,000. Enthusiasts on owner’s forums find disbelief in the idea that the cambelt change can be done for the lower figure, suggesting the parts alone cost in the region of $1,500, and that it’s a 40-hour job to do correctly. Cracked exhaust manifolds can be another source of headache too, themselves carrying eye-watering average costs in the region of $4,000 to replace.

Cambelts only last three years or 30,000 miles, too, so it’s not like this is a fit-and-forget type of job. As soon as it’s done, it’s time to get saving up again for the next go round, which can really put a dampener on the whole ownership experience.

The Volkswagen Passat is a fairly dull and easy to forget car, which is exactly what it was designed to be. It’s just a cookie-cutter sedan for those who wanted a well-screwed-together European sedan that would fly under the radar. Most are easy enough to work on, thanks to sharing their mechanical components with tons of other Volkswagen-Audi-Group models, but there is one particular rarity from the Passat universe that is an absolute nightmare to turn the wrenches on: the W8.

Essentially half a Veyron engine, the W8 was a 4.0-liter, eight-cylinder, naturally aspirated lump that, for some reason, the bean-counters and boffins at Volkswagen in the early 2000s decided was a great idea for production. It was only available for a few short years, and while it’s a treasured chapter of Volkswagen history for many, it’s notoriously difficult to work on.

It’s not rocket science to understand why, either. The Passat has been predominately four-cylinder-powered since it arrived on the scene over 50 years ago. So, cramming an eight-cylinder lump under that same hood is going to be a tight squeeze.

Enthusiasts may love them, but technicians not so much — they see them as a real pain instead. It’s been noted on owner’s forums that even some basic maintenance jobs, such as the changing of an O2 sensor, require the engine to be dropped out. Other jobs that require the same ordeal include head gasket change, camshaft replacement, and work on timing chain. Oh, and much of the front end needs removing to get the engine out, which also comes with the transmission — joy. This Volkswagen is definitely not for the faint of heart, or light of wallet, for that matter.

The ugly duckling of America’s automotive industry, the AMC Pacer has found fans thanks to its obscurity and bizarre looks, but those awkward lines have been distracting us from other more inherent issues over the years. See, initially the AMC Pacer was designed to be powered by a compact rotary engine, and by design, such engines are small in size.

The idea makes sense; a little rotary could be neatly packaged within the AMC’s compact proportions, but that’s not exactly how things panned out. Instead, a choice of six- and eight-cylinder engines were offered, and as you might imagine, cramming these larger lumps into a space designed to house a compact rotary lump meant there was little space left over for turning wrenches.

Numerous sources detail that the Pacer was always tricky to work on, and that might be a contributing factor as to why so few remain on our roads today, although we’ll wager the divisive styling was always the true problem. The Pacer might not be as troublesome to work on as some of the other cars featured within this article, but remember, the AMC hails from an era when access was plentiful, sensors were seldom seen, and plastic covers were for lunchboxes, not V8s. So, to find an American-made commuter which went against the grain was quite unusual for the time, and likely made it less than favorable with the local techies.