One of the most embarrassing things you can do as a car enthusiast is the so-called “money shift.” This sounds really dirty, but it’s simple. Often, you’re just trying to bang your car through its gears and accidentally grab a lower gear when you meant to hit a higher gear. This results in catastrophic damage and while there’s an abundance of videos on destroyed gas engines, less often seen is what happens to a diesel engine. Now, thanks to a YouTuber, here’s a look inside of a Volkswagen TDI engine that fell to a missed shift.
Volkswagen no longer sells diesel cars in America, but when it did, the company sold some great enthusiast bait. During the peak of the “TDI Clean Diesel” era, you were able to buy the Internet car enthusiast joke of a perfect vehicle. Yep, Volkswagen sold brown diesel manual wagons well into the 2010s. The Dieselgate scandal sullied the reputation of diesel worldwide, but plenty of these cars are still out there, though we’re one short after the driver of one TDI lunched their engine.
Missed shifts aren’t a new thing, but eventually, you lose count of how many people have broken apart gas engines in vehicles like Honda Civics and Volkswagen GTIs. Diesels are often remarkably robust engines, but they usually rev slower. I’m curious to see what happens to a diesel after a money shift and I bet you are too. Thankfully, the excellent YouTube channel I Do Cars has the diesel money shift gore we’re all looking for:
Our host, Eric, begins his video by telling us that it’s been hard to find one of these engines to salvage. He points the blame at the infamous Dieselgate scandal, which sent many of these cars to the scrapper. The rest remain in the hands of loyal TDI owners. Sadly, this engine wasn’t as lucky.
What you’re looking at here is a CKRA 2.0-liter four-cylinder common rail turbodiesel. Volkswagen mounted these in 2012 and newer Passats and when new, they made 140 HP and 236 lb-ft of torque. In the video, Eric says that this engine is a CJAA out of a Jetta from about 2010. In fairness to Eric, these engines all look pretty similar and the confusing engine codes don’t help. Both engines also have similar outputs as they both make 140 HP and 236 lb-ft of torque. Pictured below is what the CKRA looked like in a Passat:
And that naked engine by itself:
I was once a serial owner of VW TDIs from this generation and will say that Eric is absolutely correct when he says these cars drive great. If it weren’t for the low redline and the distinct engine noise you wouldn’t even know you were driving a diesel. These cars are also quick for diesels, too.
Sadly, Eric doesn’t know the mileage or service history of this engine, but there’s clear evidence that it had a very bad day. I mean, there is a giant hole in the block, after all. Even worse, the engine is so locked up from whatever caused that hole that Eric was able to sit on a breaker bar attached to the crank without moving a thing.
Without even getting into the engine, you can conclude that this little engine experienced an apocalypse. Still, Eric is on a mission to show us the carnage, so he gets working.
Most of the disassembly in these early stages is just a lot of getting through harnesses and lines without breaking them. Eric runs an auto salvage business, so he wants to save what few good parts this engine has left so other TDIs can live. Some things are hard to avoid, such as breaking VW’s notoriously difficult wiring harness clips.
Eric ran into a problem getting the injectors out and it was here that he learned the engine was a CKRA, but only because a CKRA has a different injector removal procedure than a CJAA. It takes Eric about 15 minutes of screen time to finally breach the valve cover. Surprisingly, the cams looked great and there was no sign of damage at the top of the engine. That’s neat!
Next, we move to dismantling the timing system. There was a bit of an oil leak, but otherwise, the failure didn’t happen here. Here’s where Eric points out the hilarity in VW’s engineering. At about the 19-minute mark, he removed all of the timing components and expected the inner timing cover to come free. However, he found that it was inexplicably secured behind the water pump.
Amazingly, carefully tearing down the engine takes so much time that we don’t even see the next bit of evidence of a failure until 23 minutes in. There, we see a second hole in the engine block with a piece of a connecting rod stuck in the hole. That rod sure got busy!
Later, Eric finds the head gasket in decent shape, but the cylinders don’t look too happy. One piston looks like it got really hot and one piston is hilariously deep in its cylinder. That’s probably the one that failed. But Eric doesn’t need to guess when he can just dig further.
As he continues, we find out that the oil filter is free of debris, but the same cannot be said for the oil pan. No major parts were found in there, but there was a whole bolt just chilling in the pan alongside smaller chunks of metal and a circlip. Eric notes that while the pan clearly indicates that a major failure occurred, there’s less debris than he expected considering the multiple sizable holes in the block.
It doesn’t take long to find the real gore. Both the oil pump and the balance shaft modules fractured into a bunch of pieces. The carnage is simply impressive and basically everything is broken in there:
An inspection of the balance shaft module shows that aside from being broken, it’s also severely bent and locked up. The damage in the block is as Eric says, “impressive.” A pile of piston pieces appeared and he found the other end of the connecting rod that punched a hole in the block.
Eric does get the engine to turn over after freeing up the destroyed cylinder three. He finishes the job by yanking all of the ruined parts out and doing an inspection. The rod bearings of all cylinders look okay enough, but the connecting rod for cylinder one appears to be bent slightly. Then we arrive at cylinder three, where all of the catastrophic damage happened. The rod fractured in multiple places, the piston broke, and bits showered out everywhere.
Meanwhile, the crankshaft had a ton of gouges and impacts, but the block took the brunt of everything with all of its splits and holes.
So, what happened here? Eric admits that he didn’t get the story on this engine. However, some investigating can rule out causes. There wasn’t enough water or rust in the engine for it to be a hydrolock event. There wasn’t enough oil or fuel in the engine either. Besides, as Eric notes, a fuel system failure would usually cause a melting condition in a diesel which didn’t appear here.
However, this engine did have a manual transmission bolted to it. Eric believes the only explanation that makes sense for the given damage and lack of other evidence is that dastardly money shift. He explains that a money shift in a diesel can cause the damage we see here, but also notes that diesel engines aren’t the same as gasoline engines.
If you over-rev a gasoline engine, you run the risk of valve float. This condition occurs when the valves do not retract and or seat properly before the camshaft lobes come back around. You can get valve float from the springs not being strong enough. You can also spin the engine over so fast that the valves just end up, well, floating. If you’re lucky, this just results in a drop in performance.
In a money shift event with an interference engine (that’s one where the pistons and the valves occupy some of the same space in the combustion chambers but at different times), there’s a chance your valves and the pistons can kiss, causing your valves to get bent. FCP Euro has a pretty good explanation by clicking here:
However, the valves on this engine look great. Eric believes this is the case since diesel engines already spin at slower speeds. At the same time, the valves in this TDI are more straight to the pistons rather than angled like the illustration in FCP Euro’s example. So he’s not too surprised the valvetrain survived the ordeal.
Even though this diesel died, there’s still some good to come out of it. Yes, the block is useless and many of the internals are too damaged, but Eric thinks many of the parts are good enough as cores and the head is good enough, too. Either way, it was pretty awesome to be able to see what the inside of a diesel looks like after such a dramatic event occurred. I’m definitely going to be thinking about this the next time I’m racing through some gears.
I also recommend watching more I Do Cars because all of Eric’s videos are a fascinating look into the terrible ways engines die.
(Screenshots: I Do Cars on YouTube)
His channel is something I watch as I am going to sleep. Not that it’s boring but it’s low engagement learning and it’s fun to see some of the quirks of different engines and look for trends as he tears down different engines from the same manufacturer or the several copies of the same engine.
You owe it to yourself to watch Eric’s videos just for the deeply satisfying sound of him cracking loose head bolts.
And cramming the cam craps
Having owned a ’01 Jetta TDI and put >160,000 manually shifted miles on it, these pictures made me really sad.
Coming off the freeway in my ’86 Nissan pickup, I accidentally downshifted into 2nd instead of 4th. Fortunately, the pavement was wet and between the rapidly climbing revs and the rear end starting to slew sideways, I realized what I had done and got back on the clutch pedal before any harm was done.
If you are trying to make it not sound dirty, maybe don’t say “bang” in the next sentence. XD
Regarding the actual content here, catastrophic, indeed. Rowing your own can bring this kind of behavior out of people, so maybe I’ll keep to two pedals for my wallets sake.
“At about the 19-minute mark, he removed all of the timing components and expected the inner timing cover to come free. However, he found that it was inexplicably secured behind the water pump.”
Yep.
I don’t know if this is more a “newer engine” in general thing or a VW specific thing, but this has been my entire experience of VW ownership. Every job requires the removal of a (seemingly) unrelated part, a new tool, and generally both. Replacing the sway bar links on my son’s Ford took about 5 minutes with a couple of basic hand tools, but the same job on my JSW took far longer and required an M6 triplesquare, which I didn’t have. The timing belt job required me to remove an engine mount as well as most of the cooling system, antifreeze reservoir, and at least a dozen other things that were ‘in the way’. To do the thermostat correctly requires removing almost the entire front end of the sar, to to it the ‘easy way’ requires a specialty tool, a few hours and the creation of some really elaborate curse words. Front and rear brake calipers are different, and require different tools to swap brake pads.
I could go on, but it’s crazy to me how everything in my car is built on top of every other thing in my car, and something that seems like a simple parts swap ends up being a 4 plus hour process of removing a half dozen unrelated things to replace the thing I need. Again, maybe it’s simply the way modern cars are, with the need to cram as much into as small a space as possible to meet emmisions/safety/etc standards, but it makes for a fairly frustrating experience. My wife’s new Mazda has only needed the oil changed, but the designers had the foresight to include a small panel in the skid plate to make that a breeze.
Side note: I was super hoping that it would be a CJAA since that’s the engine my car has, but I believe they are close enough for me to at least learn a few new tricks my car has in its bag to use against me.
It’s not just a VW thing – when I was doing the water pump on my dad’s Isuzu Amigo, removing the top section of the timing belt cover revealed all but one bolt. The remaining bolt was nestled down behind the lower section of the cover, which required removing the crank pulley to remove – what a pain in the ass. Turned what would have been a half hour job into a whole day and spending more on tools to handle the crank pulley than the cost of the water pump.
“Often, you’re just trying to bang your car through its gears” Lol! That is the best unintended, double entendre metaphor for fellow manual transmission enthusiasts I have ever read. All joking aside missed downshifts resulting in a grenade engine like this VW suck big time. One would think they could be prevented or at least reduced with an engine over speed sensor to cut fuel to the engine and an alarm for the driver. Overriding a mechanical interaction like shifting would be tricky but not impossible. Perhaps something like how the ignition system in a modern car prevents starter solenoid reengagement with the flywheel when it senses engine is running.
I check out his channel periodically. Speedkar99 is also a good one to mechogeek out on.
First time I drove a manual (car) by myself was my brother’s ’86 Acura Integra, and I managed to shift from 5th to 2nd. Pegged the tachometer. Thankfully, it took it. Honda!
You can get valve float just as easily on a Diesel engine as a gas one. While they do have lower engine speeds valve float is a function of cam profile and valve spring rate, and to reduce engine friction (and improve economy) the valve springs are as weak as they can be to avoid float (and bounce). So a few hundred rpm over the redline is as likely to cause valve issues in a Diesel or gas engine.
Back before analysis was cheap and CO2 targets were so critical you would have loads of “over-engineering” (technically under-engineering) on the valve springs. Sadly better efficiency means bigger consequences for an over-rev.
It’s the same story for bearing sizes: less friction means smaller bearings on the crank, con-rod and piston, so less load capacity to handle the extra loads from abuse. Max bearing load can be from combustion load (compressive load on the rod) or inertia (tensile load on the rod) and you get similar carnage, but the fix may be different.
One of the most fun bits of designing engines is doing root cause analysis on engines that fail in testing, as long as it’s not one of your bits that failed first. You can get some pretty catastrophic failures from a tiny issue in an unrelated system. Get the markings wrong on a dipstick and you can have the block sawn in half by a flailing con-rod when the bearings seize.
Designing engines must be/was your line of work. Your technical explanations were interesting to read. Thanks for posting. I have a friend who 3-D prints parts for Blue Origin rocket engines, and he has some pretty interesting/amusing stories about things that went wrong during testing.
Thanks! I am/was an engine designer. I love the creative bit, dork out on all the tedious engineering, and dread the testing. It was a fun career until the UK government decided ICE couldn’t burn renewable fuels and outlawed the sale of them.
People say rocket science is hard, it’s not, the science is easy: reaction mass goes that way, the rocket goes the other way. I imagine the tricky bit is rocket engineering. So many opportunities for the wrong kind of massive fireball.
As someone becoming infamous once said, “Success is uncertain, but entertainment is guaranteed!”
Non mechanic here but why do we have interference engines at all? Especially with cars that have a timing belt that needs to be replaced every 100,000kms?
Minor gains in MPG, car makers have to hit that CAFE target, and long term durability isn’t easy to sell on.
Thanks for the explanation.
Interference engines are fine unless they aren’t. It’s a tradeoff of engine performance for resistance to stupidity and to cascading catastrophic failure.
If you want a high compression ratio – which diesels require to run – you end up needing closer clearance between piston and head than the amount the valves open. Especially with Iarge and angled valves. I doubt there are any modern diesels that aren’t interference. Not that many gasoline engines anymore either.
Timing belts have lots of advantages. Cheaper and quieter, and at least some thought has to be given to changing them. Unlike chains, which even though they are “supposed to last the life of the engine” often do not. And are inevitably a huge PITA to change. I will take a timing belt over some of the nightmares that are quad-cam engine timing chains any day – with a special stinkeye to the engines with timing chains on the BACK of the motor. There is really no reason for a timing belt to fail. Change the thing on time, which is usually spec’d in both miles AND time.
Yes, Totally agree. Unlike David Tracy I don’t think 100,000kms major service including waterpump, timing belt and ancillaries belt, fluids etc. means a car is unreliable. Its a good reason to give it a really good check over and do some preventative work.
All my cars are old and have non interference engines. But I keep the belts changed before schedule. Probably why My 1988 310,000 km Toyota still has its original radiator.
If you’re a fan of your diesel starting, you need very high compression. Over 20:1 in pretty much all modern diesels, since by nature of design you need to compress the air/fuel mixture until it auto-ignites.
So unless you’re planning to make an engine with a MASSIVE stroke, it’s gonna be really hard to get that compression with enough space for the valves to still open above the pistons.
Managed 5th to 2nd in a rental diesel van once, it was possibly the worst sound I’ve ever heard. Not something I’d ever like to repeat, and certainly not ever in a vehicle I have to pay to repair.
IDK. The CKRA is an interference engine, so an over-rev would be more likely to cause the dreaded valve float which should then cause valvetrain/piston damage. This engine may have merely broken a con rod, which I think makes more sense given the damage. I don’t think anyone can prove such a scenario wrong and it is in fact probably the more reasonable assumption.
I was going for 4th and got 2nd in my old Cruze at about 60. The engine wound out to 7100 RPM. Luckily an airboat maker had already proven the engine to be fine for 7400 RPM. No damage done except to my ego.
He has loads of fun with Hyundai and Kia engines. Agree he has a great YouTube channel if you have some time.
My only missed shift in a VW tdi was in England a couple years ago. Sitting still in actual London rush hour traffic, which itself is one of the more harrowing traffic experiences in the First World, the red light started flashing yellow (I love this feature) and I slammed it into first and started off.
Backwards.
The reverse lockout on Skodas are unusually weak, especially when you’re pushing “all the way over and up” with your left hand. It’s a lot less intuitive than pulling towards you and up with your right hand (I’ve driven many, many US VW models).
A really quick Code Brown Horn from the driver behind me alerted me to my error, and I came within a few inches of their front bumper before continuing on.
At least you’re bucking the stereotype that Americans driving in the UK for the first time, will forget which side of the road they’re supposed to be on. This does happen from time to time.
I spent 6 mos in Scotland and did not have any problems driving on the left side of the road. For one thing, sitting on the right side was always a reminder that driving is different there. If I had shipped my US car over there, or had an LHD Euro car, then it probably would have been easier to forget and drive on the right.
The one exception was parking lots. I guess the focus from driving to looking for a spot resulted in me frequently drifting over to the right and receiving angry honks from other drivers coming the opposite direction.
The other issue I had is that whenever someone else was driving, I’d frequently walk to the right side of the car with the driver walking behind me having to remind me the passenger seat is on the left.
I have rented cars in Ireland and Australia. You’re right that sitting on the right side of the car drives home the point for most people. My wife did a stint of driving in Ireland and as she approached a roundabout was looking to the left as is customary in the US, and I had to yell STOP! as she started to pull in front of a box van coming from the right.
I think my mind would be far more prone to making a bad lane usage mistake on a motorcycle. I don’t even want to think about it.
My US boss came over for some meetings while I was there and got into an accident on the first day driving to the office. In his case, he was making a right turn from a B-road to an A-road and in stereotypical fashion, only looked left and not right, too.
I did the exact same maneuver in a rental VW Golf Bon Jovi on the Boulevard Périphérique around Paris, in the left lane. This was after stalling it twice trying third great from a stop. The guy behind me was laughing so hard, he couldn’t hit the horn.
I always say, if you want to learn to drive a stick, rent a car in Europe.
Of course, decades later, I rented an Alfa Giulia Turbodiesel. That was great fun throwing it around the Appenines, but I eventually realized that shifting around 3500 RPM on a diesel is not ideal. After a couple days, the car claimed it was low on oil.
I made the dreaded money shift in my Camaro, near the top of 3rd into 2nd. Rear wheels broke loose which probably saved the engine, and I got the clutch in pretty quick. Did a few track days after that without issue so it was probably ok..
Eric’s been doing a teardown (sometimes two) nearly every week for the last three years. Family friendly, lots of dad jokes and silliness, educational. Well worth the watch. He’s torn down engines out of my last two vehicles and several others I’ve owned over the years. Great way to get intimately familiar with your engine without having to tear it apart yourself.
He WILL throw water pumps. IIRC the only time he’s sold a used water pump was from a Porsche engine, but it’s one of the parts he generally refuses to sell used.
Yep, he’s an expert at cramming the crackshaft bearing bolts loose.
My favorite Eric thing is when he removes a hose clamp, quickly followed by cutting the hose
and that time he used his forklift to remove the dipstick from a Toyota engine
Or when he used the loader and forklift to get the crank bolt out of a Toyota.
Spoiler: He kept the one from his latest teardown too. Although I think it was for an employee, so probably not technically sold.
Yeah, he did. And there was one other one in the past also kept for another employee. The Porsche one, even used, was like a $300 or $400 part.
The engine probably stopped so abruptly that there was no time for the oil pump to shove any bits into the filter.
The pan, OTOH, can be gravity fed. 🙂
I read that the oil filter was clean and thought “huh, weird”, then got as far as the oil pump and thought “mystery solved!”