People either know how to work on their cars or THINK they know how to work on their cars and ultimately mess up their cars even more. These ten mechanics share the time they couldn’t help but facepalm when they saw what terrible jobs these customers did to their cars. Content has been edited for clarity purposes.
DIY Gone Wrong
“I was working at a performance shop at the time, around 2010. This Golf GTI came in for lack of power and throwing check engine codes for under boost and several for fuel trim management conditions. I did the typical process of checking the turbo wastegate operation, and pressure and smoke tested the charged side of the turbo system for leaks and tested fuel pressures. All checked out.
Then I removed the intake side from the turbo to inspect for rips in the rubber boot, all good. So, I looked inside the intake boot and this moron bought one of these ‘turbonator gimmicky’ things and put it inside the intake. It had turned completely on its side and was restricting about 80 percent of the airflow. I removed the ‘obstruction’ and motor operating values, which returned to normal, and the power was restored.
I did not feel any guilt that this idiot had to pay a few hundred for me to diagnose and remove his awesome DIY performance mod.”
He Used Wheel Bolts Instead Of Studs
“I have quite a few stories. One time, a customer had his buddy flat tow him in by tying his Ranger up behind a Jeep with a big ole’ length of rope for several miles. Not only was it dangerous, but very illegal. They were very clearly impaired. He had tried changing his spark plugs (not the only thing it needed) and managed to completely strip out the cylinder head on one plug. Then he blamed us when this basket case of an engine ran terribly when all we did was manage to get it to run at all.
There was another customer who came in with an Accord, complaining her son seemed to have done something to make it louder. We got it up on the lift and well, he had taken a Sawzall to remove a six-inch section of pipe and used hose clamps and a metal bar to keep the two sections attached to each other but it completely opened to the air. She got the bill, and he lost all driving privileges.
One guy had a beat-up Elva (obscure vintage English sports car) with residential wiring and plumbing fixes throughout. That is to say, brazed copper pipes in the cooling system with a homebrew twin, radiator setup (which still overheated), and actual residential wire and twist caps (which still didn’t work). He wanted us to get it running again for hooning about in a field. That would have required undoing literally everything he had ever done to the car, and a lot more. It left on the trailer it came in on. Shame, the Elva was literally a street-legal track car of its time.
There was this one time when a customer used wheel bolts instead of studs on his Dodge Dart. It was cheap aftermarket wheels with incorrect spacing, no hub-centric adapter rings, and had cheap ‘universal’ wheel spacers to clear the front brake calipers. Neither the wheel spacers nor the wheels were intended for use in this application with wheel bolts. The spacer had no way of centering on anything, so trying to sandwich it between the hub and the wheel while entirely supporting the wheel in the air and threading in the wheel bolts, one couldn’t help but let it slip crooked, which was what the customer did when he put them on himself, which caused it to scrape the brake caliper bracket.
It was a juggling act to get it centered enough not to interfere with anything. But those wheel bolts were still being subjected to a lot of additional forces that hub and wheel assembly was never designed for, and at some point, something was going to fail. Also, the front tires were brand new, while the rear tires were old, worn, and very dangerously low on air, basically flat.
Please, never install two new tires on the front with old, worn tires in the back. This is dangerous in bad weather, especially in the winter. If the back end suddenly lets go first, I don’t care how good you think you are, you aren’t recovering when the front has so much extra traction and the rear has none. The front tires act as a pivot and send you spinning out of control, the back tires can’t regain enough traction to straighten back out. But if the front end lets go first, then the newer rear tires can still slow the car down in a straight line long enough for the front tires to regain traction for a safer stop. If you have four matching tires of equal wear and grip, it’s much easier and more predictable to recover from a sudden loss in traction.
Conventional wisdom is really wrong when it suggests putting new tires in the front. Michelin did a lot of testing with it, and it’s our corporate policy to put them in the back for that reason. Same for winter tires; never install just a pair on the front of a front- or all-wheel drive vehicle with all-seasons in the back. We only install in sets of four winter tires, with the modestly better-mismatched pair going in the back if they aren’t all four the same.”
“About 20 years ago, I worked in an oil change shop in Northern Illinois. This one day, this red Camaro pulled up with some Florida plates on it. The woman got out of the car and said she was passing through town on her way to Milwaukee and that the engine ‘kind of has a knock to it, and it’s not accelerating very quickly. I’m hoping it just needs an oil change.’
So I started the pre-oil change service, which included filling washer fluids, checking brake fluid, power steering, and etc. I decided to pull the dipstick just to see how the oil looked. There was nothing on the dipstick. I wondered if maybe her car maybe had a leak.
I pulled the car onto the lift, and man was that engine running, but not right. So I raised the car to start service, and everything underneath looked absolutely pristine. No sign of any leaks. I was noticing that the oil filter looked like the factory filter. Now, the car has like 25,000 miles on it so I assumed she’d just been taking it to the dealership for services.
Then I opened the drain plug. Anyone who’s ever worked in an oil change shop knows the oil in a brand new car is a heavier weighted oil with a kind of green/brown color. So that was what I was seeing. I put a finger into the flow to look a little more closely at the oil in the light. Sure enough, it was factory oil. Not only was it factory oil, but there was enough little metal shavings in it that it may as well had been glitter oil.
So I went to show the woman, and said, ‘Well, part of the problem is that you for sure didn’t have enough oil in it. The other problem is that whoever did your last oil change put in the heavy grade factory oil. You really don’t want that in your engine any more than 3,000 miles.’
She looks shocked and said to me, ‘This is going to be this car’s first oil change. I didn’t know you’re supposed to change it so soon after you buy it!’
So yeah. The woman went out and spent $45,000 on a car and had no idea you’re supposed to change the oil EVERY 3,000 miles, not once every 30,000 miles.
I know that after I finished the service and pulled it out of the shop, it seemed to be running a lot better, but I have no idea whatever came of that car or that woman.”
A 4K Car For Only 785 Bucks
“I bought my car off a guy for 785 bucks. For all intents and purposes, it worked fine, but the guy said it overheated almost daily. Mind, you, it was a 1999 Nissan Sentra, manual, at 135K miles. If it didn’t overheat, it would have been closer to 3-4K dollars, maybe even more. I bought it anyway because I could try fixing it and also, I was desperate for a car. My old one died and I lived 10 miles from work.
So I brought the car home (the guy filled the radiator per an agreement we made), and the overflow tank was already empty. I started feeling along with the coolant piping, and when I came to the thermostat sensor housing, I could stick my fingernail inside the gap. My fingers came out soaking wet with coolant.
I went to a parts store, spent 10 bucks on a housing gasket, three bucks on some liquid gasket, and 50 bucks on new oil, a new oil filter, a new air filter, radiator cleaner, and coolant. Then I spent the entire day putting that gasket in, changing the oil, and cleaning out the radiator. Since that day, I haven’t had any trouble since. All in all, it’s a perfectly working car for about 850 bucks.
I kinda feel bad for the dude who sold it to me. But then again, it took me a while to fix it up and the reason for that was Murphy’s Law; ‘Anything that can go wrong will go wrong.’
You see the housing was underneath two solid pipes that were part of the AC system. That meant on top, I had about two inches of space to work with, and underneath was so curved that only my skinny wrists would fit, but without the tools. There were three bolts; one on top, two on the bottom, and my socket wrench could only move one click at a time with some fighting. Getting the bolts out took 10-15 minutes each. I put the housing gasket in, closed it, and tested it. And it was still leaking.
So I unbolted it back up, applied liquid gasket to either side of the physical foam gasket, and finger tightened it. With this, you have to wait an hour for the liquid gasket to dry before tightening it all the way.
After the hour, I went to tighten the bolts. Got one, the second, and then I turned the third four times and ‘SNAP‘. It seared right through the threading, inside the housing. So I had to unbolt it BACK up, scrape off the now ruined gasket (luckily it came in a pack of two), and get the bolt out. The bolt was sticking out one thread. I grabbed a set of needle-nose pliers (the only thing that would fit) and began the painstakingly slow process of turning the bolt with the pliers, two inches of space at a time. It took half an hour.
Luckily my old, now dead car used the same bolts, so I snagged one off of it. While I was at it and already pretty frustrated, I went and rummaged around for another half hour before finding a bolt screwdriver that was the exact right size to fit under the piping and at least mostly tightens the bolts.
Putting the entire setup together the third time took 20 minutes plus waiting time for the liquid gasket to dry.”
She Didn’t Believe Her Engine Was Full Of Oil
“I had a lady come in wanting her oil checked because she thought it was low. I checked it myself and informed her she was actually full, the oil was clean, and she was all good to go. She wanted proof so I showed her the dipstick but for whatever reason, she didn’t buy that. She wanted to see that the engine was indeed full of oil.
I tried to explain to her that’s not how it works and that it only takes a few quarts for a car her size to be good to go. Even went into detail about how the engine pressurizes itself and the oil is pulled up from the pan into the engine to do its job.
She eventually left though seemingly unconvinced because she couldn’t take off the oil cap and look down into the hole to see oil.
A few hours later, she called the shop furious because she put in a number of quarts more of oil before it was actually full and was on her way down to us in order to show us how to do our jobs.
I tried to inform her that the best option would be for her to pull over but she promptly hung up telling me she would see me shortly.
A few hours later, she called back again trying to say we ruined her car and the engine blew on the interstate because we didn’t properly fill her engine with oil.
It wasn’t until insurance refused to cover anything because she had overfilled her engine and blew the seals before seizing the engine. And shockingly it was nothing we did.
She would regularly come by the shop for a while threatening to sue and so forth. When she was eventually contacted by our attorney, she stopped coming around.
Not really sure what happened to her after that.”
The Real Life Of A Mechanic
“I was dispatched to assist a customer with a tire change. I arrived and it looked like the guy had attempted it himself.
He told me, ‘Hey man, my jack won’t go high enough so that’s why I called you.’
Okay then. So I headed over to take a look. He was using the factory scissor jack. But instead of placing it on the pinch weld like he was supposed to, he placed it under some random part of the vehicle and had punched a hole through the floor of the family minivan.
I was honestly dumbfounded at this guy. I pulled the jack out of the subframe of the van, put it under the pinch weld, and got those folks on their way. I guess they really didn’t care about the hole in their floor?
Another time there was this idiot lady who was having her son’s Jeep towed to the shop. It kept losing electrical power. She was ranting about how it couldn’t have been her son’s fault and he was a professional when he hooked up the stereo and light bars. She kept trying to get me to take her side (like I even care) that the shop kept doing lousy work and removing her son’s mods and how they were gonna pay to fix it. When I opened the hood I saw an absolutely jumbled mess of wires!
Like okay, imagine the chaos of cords behind your TV, but under the hood of a car. YEAH. It was an absolutely abysmal mess.
I wish I had a picture, but the system was being sapped with so much power because the dumb son just went overboard with the wires. Not to mention all the clutter under the hood was a huge hazard.
Another one of my other favorite customers was honest at least. I got called to tow a really nice 50s Chevy Bel Air. When I showed up, there were burnout marks in the driveway. Customer’s explanation?
‘Ah well you see I got really plastered last night and started doing burnouts in the driveway to show off to my friends. Then the transmission blew out eventually,’ he said very matter of fact.
Welp. That sucks.
Then there was the dude who tried paying me with a quart-sized sandwich bag full of joints after he had just wrecked his car into a tree on the median.
He told me, ‘I know how to deal with guys like you,’ and whipped out this bag of joints. I declined his offer.
Sorry, bud, cash or credit only. No pun intended.
Also picked up this sketchy-looking couple once. They had to pay 50 bucks in overages for their tow since their roadside plan didn’t completely cover it.
The dude said, ‘Man, we don’t have 50 bucks, but she is available,’ and the girl winked and smiled at me.
Nope, nope, nope. Bjs don’t pay my bills. I ended up leaving them since they didn’t have the 50 bucks.
That job kinda sucked, but I always came home with a story at the end of my shift.”
He Tried To Blame The Mechanic For His Mistake
“A customer brought in a car last Wednesday with a shaking issue. Cool, so I took care of some of the issues the car actually had, which included, bad axles, TSB on the diff, dirty transmission fluid, blown rear shocks, and of course, a need for an oil service. The car left 10 times better. It was done and gone. We listed the recommendations still required but the customer declined, only did the axle and diff fluid service.
A couple of days later, we got a call from the same customer.
Customer: ‘What in the heck did you do to my CAR?!’
Me: ‘What’s the issue?!’
Customer: ‘The issue is back, and it’s freakin’ 1000x worst! What the heck did I pay you for?!’
Me: ‘Ok, well if it is our repair that caused the problem, then we are more than willing to see what’s going on. We didn’t replicate anything after the test drive, so unfortunately we can’t determine if it’s the same issue without checking it out.’
Customer: ‘I demand a tow truck to be sent out and you guys HAVE to flip the bill on this. I’m not paying for this nonsense.’
Me: ‘Sir, not a problem. If it is work we’ve done, we are happy to pay for the tow and correct the issues. But be advised, if the issue is due to the OTHER recommendations or a new issue, you will be responsible for the tow fee.’
Customer: ‘Yeah that’s fine. I know it’s what you guys did anyway.’
Me: ‘Okie dokes, a tow truck will be there within the hour.’
So in an hour, the tow truck picked the car up and the tow driver immediately noticed the issue. There was a puncture on the rear right, outer tire sidewall. It was a nice welt and gash the size of a penny. The tire was completely deflated, so the driver told the customer and noted it on the receipt. The customer acknowledged it and signed off on it.
So when we got it back to the shop, I grabbed an air hose, hooked it up to the tire, and just like that, the air started wheezing out. So I called the customer.
Me: ‘Yes sir, you had a flat tire, and you were driving on it.’
Customer: ‘Nope, not possible, it left here fine! And I barely drove it home and it sat since I picked it up from you guys.’
Me: ‘According to the receipt, you acknowledged the puncture WITH the tow truck driver and signed it off knowing it was flat. But we did install the spare, drove about 10 miles on the street and freeway, and we cannot replicate the issue at this time.’
I could hear the customer trying to find the receipt, and then he hung up
Guess who just paid the 75.00 on a tow bill.”
Some Common Minivan Maintenance Or So He Thought
“A woman came in for an oil change and some common minivan maintenance, but nothing out of the ordinary. I walked by the van while it was upon the rack, and noticed one of the tires was nearly bald in the middle, cords showing; basically textbook over-inflation.
I checked the tire pressure, and it was well over-inflated. Then I looked around the vehicle and saw two more tires were in exactly the same state, over-inflated and showing damage from it. The fourth was a bit under-inflated, with no glaringly obvious tread wear.
I pointed it out to the customer when she came back and asked if there was any reason three tires would be over-inflated. Long story short, she was occasionally seeing a ‘low tire’ light on the dash (no indication of which tire, just ‘low tire’), told her husband, and he just aired up all four tires. It happened again, and her husband ‘fixed’ it the same way. Rinse and repeat.
So over time, they kept the tire with the leak going but managed to ruin the other three.
Tip: Buy a tire pressure gauge if your car doesn’t give you per-tire pressure readings.”
It Was The Newest Trend In Town
“Some years ago, here where I live there was a fairly widespread craze of mixing oil. I don’t remember the type, but it wasn’t at all related to the engine like sunflower oil or something like that, but with diesel for better fuel consumption.
The thought was that this type of oil would burn anyway, and mixed with diesel it would give the same kilometers for less money.
Of course, it wasn’t the brightest of ideas, so I remember that despite being fairly young, I remember strongly advising against this practice. My mother didn’t listen to me and proceeded to top her Mitsubishi Pajero Turbo (great car for fuel economy, I know) with whatever oil she used.
Now, to be fair, the car held up pretty well despite the abuse, because it was a tank, however, it eventually succumbed. If I remember correctly the fuel pump completely failed and had to be replaced entirely, but I might be forgetting stuff. The funny thing is though that the mechanic, after looking at the engine for about three minutes or something like that, asked almost angrily to my mother if she was using the oil.
When questioned how he knew that he said something along the line of, ‘It’s the fourth this week that comes in with this issue.'”
How Did This Brand Corvette Die On The Road?!
“I worked as a car cleaner at a dealership one summer in high school. A guy towed in a relatively new, top-of-the-line Corvette he had bought there sometime before I started. He was extremely ticked off that it had died on the road and been running terribly before that. He ranted and raved about he spent all this money and it only went X amount of months/years before completely breaking down.
One of my work buddies got it up on a lift and started looking it over. He opened the oil drain plug and NOTHING came out. He pulled apart the engine and the oil could now be best described as glue.
The owner talked to the guy and asked when the last time he changed the oil was. The guy had zero idea what he was talking about. He had no idea that you had to do that. He assumed you just added gas and that was the only thing you needed to do. The engine was a complete loss, which meant the car was a complete loss to him.”