Engines! We expect them to do so much these days. We want them to fling us around on our errands for hundreds of thousands of miles, sipping the bare minimum fuel all the while. That’s simply the bare minimum these days, but some engines fail to meet these demands in a grand fashion. This leads us to our question today—what’s your most hated engine design flaw?
Try as they might, sometimes automotive engineers get it wrong—and an engine ends up with a fatal flaw. Months or years down the track, a poorly designed part lets go, or wear hits some critical point. Suddenly, dealerships are getting bombarded with calls, forums are melting down with rageposts, and the automaker is left to arrange repairs via an expensive recall campaign. Or, hell, even buybacks!
You would think that automakers would catch these problems in testing. After all, new engines and new vehicles typically go through millions of miles of testing before they ever hit the road. And yet, somehow, this still happens every few years, even to automakers with the best reputations for reliability.
Earlier this week, we were talking about a controversial example—that of the Cummins 6.7-liter diesel. Listen to some, and they’ll tell you the engine will gladly ingest a poorly-placed nut, munching itself to destruction in the process. Listen to others, and they’ll tell you it’s an incredibly rare ocurrance. It might have never led to a recall, but it’s a compelling tale nonetheless.
Other situations are more cut and dried – for example, when Oldsmobile engineers tried to make a diesel out of an old gasoline V8. That engine had drastically underrated head studs that meant head gasket failures weren’t just a possibility, they were a near certainty. Because of that decision, many car buyers saw diesel as a devil fuel in America for the best part of a decade afterwards.
You might also tip your hat to Lancia. The company famously built an engine so fragile that you could destroy it with a simple turn of the steering wheel. Properly Italian motoring, right there.
We love digging into weird engineering topics, and often it’s the quirky little failures that excite us—and you!—the most. So do tell us—what engine is your bugbear, and what is its fatal flaw that should never have made it to production? We’re absolutely dying to know what has your motor dying. Sound off below!
Credit: GM, Cummins, BMW
GM 1.4 turbo Ecotec has coolant lines running from the engine to the turbo……. Between the engine and turbo, and under the exhaust manifold. They’re rubber hoses. They last about 30-40k miles before the extreme heat of this location absolutely roasts them and it gets a coolant leak. Replacing the lines requires removing the turbo, so >$1000 labor to replace $20 of hoses.
Not to mention their propensity for the turbos themselves failing, and the valve covers having issues with the integrated PCV system, and the intakes. Ugh.
I’ll add another one, which is the Ford SOHC 4.0L timing setup. There are timing chains on both the front and rear of the engine, both of which use nylon tensioners and guides that wear out around 100,000 miles. The front tensioners and guides are easy to replace in vehicle, but the rear require an engine-out to get to. I’m currently dealing with this on my project Explorer, much to my frustration…
Couldn’t agree more, worked on a lot of these when they were pretty new. Ford updated the tensioner designs which did help a bit… but still it was a garbage motor.
What makes me mad is that Ford already had a fully baked, proven, and even on it’s 2nd gen version of the SAME V6 (Cologne V6) that had DOHC instead of SOHC… and the DOHC version had all the chains at the front of the motor.
The DOHC wasn’t brought to the U.S…. only for the Ford Scorpio in the UK/EU.
Wanna be more annoyed? All the Colonge V6’s came from the same factory in Germany.
So Ford could have absolutely put the DOHC version in the Explorer/Ranger and had a class leading V6 engine at the time.
Yeah, I recall some excuse about the DOHC not fitting in the same spot as the 4.0L OHV engine it was (sort of) replacing. Still frustrating.
They coulda but didn’t wanna apparently do what they did on the sn95 mustang when it went to 4.6 power, changer the brake booster to hydro boost because it was too wide and wouldn’t fit.
Ford logic at its best
I had one of those mustangs and the brakes had a horrible mushy feel due to the hydro-boost + the master cylinder design. Braking hard from over 60 mph would cook the brakes and the make the pedal go soft almost every time. This is after upgrading the fluid, new lines, calipers, pads, and rotors.
Weird, drove a buddy’s wife’s gt, and it had some pretty good stoppers on it, pedal was a bit different than my crap, but felt ok otherwise.
But… Ford will ford
Yeah idk cuz I drove a few other sn95s and they all had different pedal feel. Mine was sensitive but soft and had a long travel. Others I drove felt like the brakes pads were made of wood. It was pretty odd but I guess it’s just a quirk of that generation mustang.
They are rather odd, still want an early one to irs swap and go corner carving
Rear timing chains are just a terrible idea in general. Dropping the transmission to do timing guides shouldn’t be a thing ever.
Indeed, such a bad idea. I wish I could just drop the trans, but in the Explorer/Ranger the firewall blocks access to the rear timing cover, so engine-out is the only way they can be done.
You can cut out the firewall if you are feeling adventurous and you already have your interior disassembled. Just don’t do it on your daily it takes time.
Yeah, I’ve owned a bunch of 2nd gen Explorers and pulling the engine is the better plan, as when it is time to do the guides it is also time to do other things that are far easier to do with the engine out like rear main seal and valve cover gaskets (and upper intake gaskets, though those are easy to do in-vehicle). The problem I am currently having is even fixing the 4.0L and instead just doing a V8 swap from a donor Explorer.
This is not specific to one OEM, but it absolutely makes my blood boil.
“press fit” gears on crankshaft, camshafts, oil pump drives, transmission internals… or anything critical.
The idea that the tolerance is so small that the gear will hold precisely in place on a shaft due to interference (instead of having some sort of keyway, etc. to hold it exactly in place) so a fucking supply chain and/or manufacturing executive can get a bonus for NOT paying the couple of pennies per engine on machining (?!?!)
Notable examples:
Ram/Jeep Ecodiesel V6’s have this design on cam gears, and it has failed for some people… in addition to the buckets of other failure points on this stupid engine.
Ford/Yamaha V8 SHO – Pretty much all of them will jump time (if it’s not remedied) because the cam gear will move out of time with the camshaft it’s on due to “press fit” cam gears. Then the motor is toast. I had the “pleasure” of replacing one (under 100k miles, well maintained) and it sucked so bad I think it was the most PITA motor swap I’ve ever done. I would gladly swap over any other ford product engines than this again.
Ford’s 6.7 Powerstroke diesel – Can’t blame this one on Navistar like the 6.0/6.4s! It supposed to be a heavy duty V8 diesel, and as such it has gear driven cams (hell yeah)… but the crank gear on certain model years can actually move out of time. Luckily it forces some rough running and a check engine light before explosion.
I know there are more issues from this specific design across other engines/transmissions… curious if anyone else knows of other ones.
It’s a stupid idea and it should go straight to hell.
I really hope to learn more about the 6.4 PS someday, hopefully in an article on here. I heard they’re worse than the 6.0.
I worked at a Ford Dealer when 6.0’s came out… and within weeks we were replacing stuff on them.. they are bad. However… the 6.4 is a bit worst in a way.
Later years 6.0L’s if you do upgrades to them, maintain them well, some will live long, although I still don’t like them and wouldn’t recommend them to anyone.
6.4’s have sand/particles in the block that loosen up over time, oiling issues in the heads, front cover issues, etc…. and even if you upgrade 6.4’s they just never seem to live long lives.
So… overall.. 6.4L’s are a bit worse for longevity, but it’s really arguing about which bad engine design is worse.
The 6.4 is so bad that a well known Powerstroke specialist shop in Georgia (Powerstroke Specialty in Buford, GA; known on YouTube as PowerstrokeHelp. RIP Bill Hewett) refuses to touch them because of all of the issues and the lack of rebuildable core parts.
Yikes…
Hey now. Press fit is how I still manage my way into 32’s.
hahaha I also “press fit” in to 32’s
Preach! Bmw S55 engines have that particular flaw, apparently bmw engineers didn’t foresee m3/m4 owners wanting more power out of them. Literally a couple more horsepower will spin the crank hub and send it out of time. Just dumb.
The very early Neon engines had a fun one: head bolts that bottomed out in their holes before they reached torque. The engineers spec’d a certain thickness of head gasket, and the bean counters changed it to a thinner, cheaper one, and the result was a great big mess when the head gasket started leaking oil externally. I aaw it happen to one early on. God that was a lot of oil spewing out of that thing.
Best part of that, was that they knew the head gasket was not going to work. The engineers told the executives as much. The executives asked how much extra is was going to cost to upgrade to the proper gaskets. The answer: $1.00 per car.
That was too much for the executives, who then immediately nixed the fix, and sent the Neons out, as is.
Cadillac 8-6-4 anyone? Or to go a little more obscure, the brazed block in the Crosley Hotshot.
The “COBRA” engine. (COpper BRAzed)
The only thing that was an issue between Carroll Shelby and the name he wanted for his new roadster. When Carroll went to trademark the name “Cobra” for his car, he discovered there was already a “COBRA” trademark registered in regards to automobiles.
Luckily, Crosley hadn’t used the name in a long enough period of time, that the trademark office decided to let Shelby have it.
In a similar vein to the Cummins example, apparently gen 3 Priuses (2ZR-FXE) are known to blow their head gaskets, but there’s no recall and it’s hard to tell based only on internet anecdotes how common it is.
Not to mention I don’t even understand the cause of the problem. Some have said you can delay it by making sure the EGR system is cleaned out around 140,000 miles and every 40,000 miles after that, but other say it only postpones and doesn’t prevent it from happening anyway.
My anecdotal experience is that it seems quite common. Some also argue that adding an oil catch can between the engine and the intake manifold can help avoid this issue, but seems like evidence is not conclusive.
I thought that the electric water pumps go out on these and don’t provide ample warning before it’s cooked. Head gaskets are almost always just a symptom of something else going wrong
What I hate is that I’ve asked for quotes to get the pump preemptively replaced, but I’m told the car has three and I don’t know which is the trouble one or else I’d be happy to do it.
Gonna go with the rear timing chain setup in various Audi’s – hell even the front’s where you have to take the entire snout off to service it. <Insert that picture that we all have seen before here>
Just VAG engines in general make me shudder. Ugh.
Had a 1980 (?) Chevy Malibu station wagon. Black with red interior and simple pin stripes in red and a set of Cragar mag wheels. Good looking wagon. Had a V6 that ate the camshaft every six months. Like clockwork. After 3 or 4 years I gave up on it.
The BMW V8s with the o-rings on the coolant pipe that fail and cost $3 in parts and several thousand in labour to fix comes to mind.
The Hyundai engines that fail with the frequency of a cheap ham radio are another example.
And the threads for spark plugs on the Ford 5.4 engines….”yeah, four threads oughta hold just fine.”
The Taurus SHO V8 cam gears.
AMG head bolts.
VW cam followers. And timing on VR6s. And anything to do with the Phaeton.
Any modern BMW.
Any and all timing belts and interference engines.
Mid 80’s Chevy small blocks using nylon camshaft sprockets. That was a fun one.
Hard to call literally every Honda engine flawed when they are a paragon of reliability and longevity.
Nylon cam sprockets aren’t just an 80s Chevy thing. Really common on lots of pushrod engines from the 60s-90s, and legendary Ford 300s have plastic cam gears that normally last like 400k miles.
Funny you should mention Honda. I had an 87 Acura Integra grenade and bend valves literally the day before I was going to bring it in, well before recommended replacement mileage I might add, for a new timing belt. It went from a $250 job to over a grand. So, yes, it’s a very flawed design if a belt failure results in an entire valve job. Reputations for reliability and longevity have nothing to do with the question. The question was about a design flaw. If you’re going to knowingly design an engine to have potential interference between pistons and valves then you better make sure that something more substantial than a rubber belt is keeping that from happening. Someone over at Honda did not do their 6 Sigma FMEA.
Interference engines. Not even once.
My beef with 80 and 90s Hondas is having to do mechanical valve lash adjustments, something I learned to do an a 71 Triumph TR-6 and figured would never do again. Had no idea it was a maintenance item on my 89 Civic and burned an exhaust valve at 180k miles. Keeping on top of it with the 94 Accord.
They had solid lifters up until very recently (maybe some model even still has them, I stopped caring enough to follow)! That’s one reason I never got into Hondas. I’ll adjust valve lash on an old engine or something cool that’s a weekender, but not a daily driver when its contemporaries long before went hydraulic (of course, those competitors also built engines that made enough torque that they didn’t have to rev to 8k to make some mediocre hp rating, but at least we got variable valve timing into the mainstream). They also hung onto distributors for a while.
The Accord was a hand me down from my Mom but it has soured me on Hondas, in general. The Accord also has captive brake rotors, instead of ones that simply slide over the wheel studs. Another stupid design. Not looking for the the brake job on that…
I thought they handled and drove nice with minimal mods, though.
My 2010 4.0 Taco had solid lifters (I’ll bet a lot of Taco owners don’t realize that). That wouldn’t be so bad, but the amount of dissembling required to get to them is unconscionable. Remove intake, and a bunch of other stuff to get to the valve covers, remove covers and I’m not sure what else to get to the shims. I started on it at 100K miles, then said fuggedabouit, and let it go. A small factor that led to my selling it a few months later.
And they were shims, too? Yeah, that’s ridiculous and it’s not like they’re high-rpm engines.
Yeah, they implied that you replace the whole lifter, but I believe they were shims. Kinda a dick move for even a DOHC engine that requires removal of so much of the ancillary components to even get at the valves. The only engines I’ve encountered w/ shim adjusted valves required removal of the cam, or had rockers that required removal of the rocker shafts. The Ford (among others) has a hydraulic pivot point that adjusts the clearance between the rocker and the cam. It would work a treat in the 1GR-FE.
I had an 89 Civic SI SOHC. Valve adjustment was as simple as pulling the spark plug wires and the PVC hose, undoing 4 nuts and lifting the valve cover off.
Well, I just looked on line, and it’s the whole lifter and you have to remove the cans, ‘cause the lifter bucket sits on top of the valve. Apparently, it is a 250k motor, then throw it away.
GM used nylon cam gears as far back as the 60’s. It was good for us though as Karen’s 68 LeSabre would start running like crap by around 50,000 miles so we’d buy it for +- $500, put a steel gear on it and off we’d go.
Had a Dodge van w/ a 318. When the wife shut it off at a store, the timing chain & sprockets were so worn, the chain fell off the bottom sprocket. At least one valve was bent on trying to restart it. It was cheaper to buy a low mileage 360 than to repair the existing, worn out engine or buy a 318. W/ headers, an Edelbrock torquer manifold, Quadrajet carb and Hooker headers, it didn’t get much worse mileage than the tired old 318.
Was going to say the same on the chains/belts on interference.
Chevy was not the only one doing the nylon cam sprockets. And they all fail w/ distressing regularity.
Not necessarily an engine design, exactly, but I’m going to pile onto the Olds 350 Diesel with the lack of fuel filtration. GM fixed this in later diesel engines with diesel fuel filters with water separators, but did absolutely nothing for the Olds 350 in any application. The head studs were definitely a problem, but back in the 80s when fuel stations also lacked filters, bad fuel would stop the engine well before the head gaskets could let go. I have not-so-fond memories of emptying the fuel system and pulling glow plugs to empty the cylinders of my mom’s ’82 Buick diesel after it ingested bad diesel, and then struggling to prime the fuel system again.
I think the Cosworth Vega had an open deck, which is one. Then a cast iron head and aluminum block, perhaps before MLS gaskets. It would’ve been wonderful to see that engine developed if it was started off right. The coated cylinders probably didn’t help either. Lots of good but undeveloped ideas.
Also, the Willys Tornado 230. It took Argentina, Renault/IKA to put seven main bearings in an engine that should have already had them. Mostly I just bewail the fact that I can’t have one of the later IKA engines in a Willys pickup.
Also, Ford Cleveland priority oiling.
Also, I think all headbolt holes should be blind.
The first 1.5 years of NA miata 1.6L engines had a very short nose on the crankshaft, which, inevitably, when the crank bolt was ever loosened for a belt service or pulley replacement, is nearly never torqued enough, resulting the key on the crank gear to be worked side-to-side, eating away at the keyway of the crankshaft itself, requiring dubious fixes or an entirely new crankshaft. The later 1.6 engines got a “long nose” crank that alleviated the issue with a longer crank nose, meaning if the crank bolt wasn’t tightened enough, the key/keyway could at least accommodate the loads.
It’s a pretty stupid problem for what is otherwise a really solid engine, and a really reliable chassis as a whole. And while it is fixable and preventable, replacing a crank gear that rusted itself to the crank nose is a nightmare, as I found out the hard way.
I wonder if that was a result of a service book misprint. Same thing with the EJ22 in my mk1 Legacy. Published spec in the usual aftermarket manuals was way below what it needed to be (85 vs 120 ft/lbs or something like that), though I think the factory manuals had it right, that’s too long ago to trust my memory. Luckily, when my crank pulley came off, the pulley took the brunt of the damage and the crank was good enough to take a new key.
Well I’ll be damned. I had that same near-catastrophe thanks to blindly following the torque specs in the Chilton (or was it Haynes?) manual for the harmonic balancer on my EJ22 ’99 Legacy. I caught it before it grenaded, the car was parked idling and I was looking at the pulley and wondering why it was wobbling. The woodruff key was too chewed up to remove the pulley so I had to take it to my local trusted mechanic to fix it. That was my first and last stab at doing my own timing belt too, never again.
I think I had a Haynes for that car, but it might have been an issue with both manuals IIRC, since we found the problem out on an old school forum when multiple people had the problem. That’s when I decided to buy the factory manuals, which cost so much that I’ve kept them over 20 years later.
I made a cam sprocket lock out of angle iron and some U bolts, which made belt changes a lot quicker, though at the time, it wasn’t that expensive to pay to have it done.
The cam lock would’ve been a nice addition to mine, but I sold it soon after. Despite being fixed, the harmonic balancer still had a perceptible off-center wobble. Also, one extraordinarily cold morning while visiting N Georgia, I started the car, and it made loud rod knock noises. The sound went away as it warmed up, but I’d made up my mind: I was selling it. It wasn’t until it was gone that it dawned on me the noises I’d heard that one frigid morning were piston slap, duh.
https://imgur.com/gallery/answer-is-always-subaru-legacy-wagon-Dn5wOt2
The gen 2 EJ22s had piston slap problems, too? I thought that was just the awful 2.5s.
Ford Y-block required external plumbing to fix a top-end oiling issue.
The entirety of the Oldsmobile 350 Diesel
In terms of consequences, I gotta go with the Northstar’s wussy-ass head bolt threads. Too skinny to hold on during higher-heat situations, they let go and terrible things happen. This engine was so bad that people wanted them to start producing the HT again. Maybe the single biggest reason Cadillac is a shadow of it’s former self.
In a more general sense, interference engines with dicey timing drive systems. The interference part is in pursuit of efficiency, but the reliability cost seems too high.
The worst part is GM eventually got decent head bolts in the Northstar. The final generation uses LS head bolts and don’t have head gasket problems. So naturally GM ended the engine a few years later.
Where do I start?
Let’s begin with the DISI MZR Mazda 2.3 turbo. Maybe it was the turbos that over-oil from the factory and blow seals? Maybe it’s the timing chains and VVT actuators that poo poo themselves at the same intervals as most timing belts are swapped. Perhaps it’s that the engine is an interference design, but the timing assemblys are held together with friction washers instead of a keyed crank. Oh wait! Nope, the worst part is the factory high pressure fuel pump that randomly goes full lean on WOT, and blows up the engine. ZOOM ZOOM KABOOM!
How about the 3VZFE 3.0 V6 from Toyota? Or the 7M engine, also from Toyota. Both ate headgaskets for lunch. The 7M just needed the head bolts tightened; apparently the 3VZ needed the exhaust re-routed to fix the HG issues. Still, wild for a company who’s reputation is built on reliability.
How about one that everyone knows (and some love): The HEMI! The cams eat themselves to oblivion if you have high idle time… You know what idle a lot? Cop cars and construction vehicles, which are main markets. The Pentastar 3.6 also has that issue.
Oh, speaking of Cummins, how about the 5.0 they put in the Titan XD’s? Apparently, a snapped CRANKSHAFT(!) is a common issue. Hot dang!
Now Subaru… the engines are flawed from the factory, but I have a special hatred for the EJ255 that came in the mid-00’s Legacy GT and Outback XT. They have 2 fun problems: a filter screen in the turbo feed line, and a catted up-pipe. Both can cause the turbo to grenade, and take out the engine with it.
All engines have an Achilles heel, but these are ones I’ve witnessed/heard of that blew my mind.
The 3VZ is a good one. My dad had two company vehicles with the 3VZ that needed head gaskets before 100,000 miles. Admittedly, both went another 200,000+ miles afterwards without needing head gaskets again, but it still wasn’t in keeping with Toyota’s reputation.
The MZR is a motor I’m not super familiar with, but I do know my friend’s Mazdaspeed6 went through two timing belts in two years, with the second one requiring a full engine replacement. Luckily, he was still under warranty for all of it.
***timing chains (!!!)
Whoops, I meant chains and still typed belts. Doh!
Definitely the Hemi.
Like, seriously, it’s an OHV engine. It’s the only kind of engine they built for nearly 40 years; how do you screw it up now?
Apex seals.
Related, the rubber water jacket seals on the 71-73 12A that would fail after 30-40k miles and leak coolant into the combustion chambers while not running and hot combustion gasses into the coolant when running. Kind of liking making a head gasket out of rubber. I think most of these engines were replaced under warranty.
As far as rotaries go, apex seals get the jokes, coolant seals actually kill the engine.
Yes, apex seals do fail, but after a certain point, in stock form (i.e. not boosted to the moon), that wasn’t the usual killer of a rotary.
Gotta give some love to GM’s LT-1 V8 with it’s OptiSpark distributor. Not a terminal problem, and I’m sure it was an altruistic attempt at “good” engineering by creating a new type of distributor that’s rotates more closely with the engine…
But making the distributor a plastic disk that mounts behind the water pump?! WTF GM!
Having changed more than my fair share of Optisparks, the fact that GM used crap gaskets that did little to waterproof them was the real problem. In theory, a little moisture wouldn’t be a problem, as the vacuum connection should remove it, but when the water pumps went (or someone hit them with a hose), the Opti just couldn’t help but collect the moisture and stop functioning. The actually waterproof aftermarket Optisparks from folks like MSD helped considerably, but by that point the damage was done and everyone turned their attentions to the LS motors.
The rest of the LT1 engine control system was cobbled together, too. Precise ignition timing information could have fed a waste spark or coil-on-plug system rather than the troublesome distributor. The fragile optical sensor didn’t need to be near the arcing plug wires. The ignition coil used a separate ICM rather than the integrated coils more typical of that era. Multiple temperature sensors feeding different readings to different parts of the system (took me a while to figure that one out).
The reverse cooling system was also a bit odd.
It looked like a hot rod shop had thrown a bunch of speed parts at a small block after the fact, rather than a purpose-built drivetrain from a major OEM.
What was annoying was that GM already had years of experience with distributor-less engines (3800 V6) and it wasn’t like it would have required a lot more parts.
Probably not the worst or most egregious, but I always felt the pre-cats in the MR2 Spyder that could disintegrate and destroy the engine were especially sad.
Here is a low-cost fun car using what is virtually a rock solid Corolla powertrain off the shelf, and there is still a common catastrophic failure point.
Early 00’s Nissan 2.5 had the same issue… RIP many Sentra SE-R’s
When I bought a 2005 Spec V the first thing I did was ditch that stupid pre-cat and put a header on it.
Nissan 5.6L V8’s have a similar problem.
Wonderful engine with a stupid achilles heel sheetmetal “catifold” design bolted to them that costs lots to replace, and 100% of them crack, and if people drive around with them cracked long enough because they don’t want to replace them… boom… new engine.
Same with the 4L V6 used in the Xterra / Frontier / Pathfinder.
YEP! Seems like Nissan is very good at this…
Can you expand on how a cracked exhaust manifold blows the engine?
Sincerely, Titan 5.6 Owner With Codes 420 & 430.
There’s a couple of issues going on. The 1ZZ-FE had undersized oil return holes in the pistons which clogged really easily leading to oil burning. This wasn’t fixed until very late in the engine’s life (late 05) with revised pistons. Both of mine had perfect precats but used 5w30 like it was going out of fashion
The stupid R53 Mini motor that has a PLASTIC thermostat housing. On the back of the motor. Against the firewall.
Thermostat housings should not be “wear items”.
Sounds about right for BMW; plastic timing chain guides come to mind.
Agreed. It wasn’t as bad to get to, but my Cruze has a crappy plastic housing too. Most cars do now.
If BMW can figure out a way to make it out of plastic, they will.
Also the ’07-’10 R56/57/58 with the N14 engine and its shitty timing chain guides/tensioners ON TOP of all the plastic cooling pieces, including the thermostat housing which I replaced literally every year, among other shit: 3 turbos plus recalled oil feed lines, 3 diverter/blowoff valves, plastic valve cover/gasket cracking, constant vacuum leaks due to broken plastic fittings, and on and on. I’ll NEVER buy or drive another BMW product after that one, and I suspect I’m not alone.
You almost never see one of these cars anymore because all the engines blew. I had a really nice one, and sold it with 90k on the odo because I had a panic attack about it blowing up every time I drove it. Sold it, bought a 20 y/o Boxster S that’s been rock solid and haven’t looked back.
There’s 2 types of people: those who’ve owned a BMW and never will again. And those who have yet to own a BMW.
It’s hilarious watching old Top Gear episodes where they talk about how reliable certain cars feel and will be and then years later knowing what we know now about those models.
Say what you want during a week long test drive but don’t ever mention reliability, always irks me.
My Explorer with the 4.0 V6 had a plastic thermostat housing too, which predictably started leaking. At least it was on the front of the motor and easily accessible
Damn it, I immediately thought of the Gamma, but you beat me to it. For pure heartbreak, I will say Porsche IMS bearings. Affected cars are now over 20 years old, but I still break a few hearts every year when I tell owners they have a catastrophic failure, usually in a car they long dreamed of owning. These are cases where I use my Extra Soft And Gentle Voice.
Ones like that that are so well documented and don’t get a recall amaze me.
Cylinder distortion in the Vega due to the sleeveless aluminum cylinders, but there were so many other issues with that car too.
You’re aging yourself w/ that comment, and I will too. The die-cast block with an open top, with any weight savings cancelled out by a huge iron head, must have been crazy fantasy at GM, thinking they could make that work. Nearly every single one failed between 20K and 70K which means I could buy cool engine-swap candidates for a couple-hundred bucks for years. Bizarrely, I had a ’73 GT that I was planning to drive ’til the engine quit, instead, as long as it was fed oil it was an excellent car in operation and reliability at 125K and 20 years old when I sold it as-is so I know it was possible.
Yes… there were plenty of problems with the Vega besides the aluminum sleeveless engine with a cast iron head. Rust? The horror, the HORROR! But those engines have to make at least the top five list for worst.
there were over TWO MILLION Vegas sold over about six years. However, I honestly have not seen one since about 1980 – if YOU DO see one, it will have been turned into a drag racer with a V8.
However, there is always an exception that proves the rule:
eBay Motors does list a lone Vega for sale…. a 1975 Cosworth Vega with 59,000 miles .
Two points-
technically the engine is not really a Vega engine.
This was the finest example of a Vega ever sold… and -in excellent condition- the seller is asking only $13,500.
There are two Cosworth shells near me, it’s really the only way to find a Vega. All the regular ones were scrapped long ago. For Sale “cosworth vega” near Ramona, CA 92065 – craigslist
GM Active Fuel Management! An engine design that involved their paying customers to be involved in the R&D program for 40+ years. AND they never got it right!!!
No one has figured out the reliable shutting off half the engine a cruise technology. Heck, even Honda Odysseys are less reliable because of it.
the v6 in my 2017 Colorado seems to work well when 4 of the 6 are running. 60k miles and I am ignorant of know issues.
This was my vote, but you beat me to it.
The flat 4 in the Lancia Gamma absolutely has to be it, in that the engine could be completely destroyed due to the owner doing something completely innocuous and normal
But, Motors Liquidation also has some on the list – the HT4100 had too-soft aluminum blocks that the head bolts would pull loose out of, weak camshafts, and head gaskets failing due to being unable to withstand the differential expansion/contraction of the head and block, along with other issues. It was rushed into production against engineers’ objections that more development was needed, and the enlarged and rebranded 4.5 and 4.9 derivatives ended up being very reliable
Also, the Northstar, with too-short head bolts that worked loose over time, and took them about a decade to fix, despite a mountain of evidence regarding engine failures
Don’t forget, aluminum block and iron heads! Can’t imagine why they didn’t just go with aluminum heads too. You’re already paying that much for an aluminum block, just finish the job.