10 Serious Mistakes in Car Maintenance

There are a lot of dangerous, irresponsible and downright ridiculous things you can do to a car while "fixing" it.

When a car does what it's supposed to do, it's pretty easy to take it for granted. But things can (and do) go wrong with no notice at all. Sometimes parts fail without any kind of warning -- without a grace period that would let you know something's wrong so that you might have a chance to fix it. But let's face it; most drivers are guilty of ignoring problems with their vehicles at some point or another. And that's the first (potentially) fatal flaw. But it gets even worse when the problem is "fixed" improperly. We've compiled a list of some common car maintenance problems to watch for, whether you service your car yourself or even if you pay a pro to do it for you. And don't worry, it's fine if you choose to outsource your car care -- we won't judge.

No.1 Roaming Around with Burned-out Lights

It's relatively simple to replace your car's headlights.

Compared to most other car maintenance, it's relatively easy and inexpensive to replace light bulbs. So do it. You should know pretty quickly if your headlights or high beams burn out since you won't be able to see, and the turn signal indicators on your dash should clue you in if something's wrong there. Running lights, taillights and brake lights aren't quite as obvious, so just take a look every now and then.

And when they do burn out, pull out your owner's manual and replace them. It's not hard; it's not dangerous. Getting pulled over for a burned-out light is just extra stress you don't need, and getting hit because another driver couldn't see you is just ridiculous. Both of these likely outcomes will be a lot more expensive, too.

No.2 Attempting a Jump Start Without Really Knowing How

So easy, even a dummy can do it.

Putting jumper cables in your trunk doesn't mean you automatically know how to jump-start a car, but at least you did it before your battery died, right? But if you don't use jumper cables properly, you can fry your car ... or yourself. Though the procedure is really simple, you should learn how to do it before you actually need to. Not standing on the side of the highway while reading this article on your phone. That's dangerous.

Here's the stuff a step-by-step guide might leave out: First, get out of the way of traffic. Common sense (or self-preservation instinct) should tell you not to smoke. Less obvious, but otherwise logical, you should wear eye protection, make sure the two cars are parked so they're close but not touching and ensure no cables or connector ends touch anything other than the correct terminals. Don't keep cranking if it doesn't fire up -- just give it a little more time. And make sure the ignition is switched off in both cars before you start attaching cables. Even the dead one.

No.3 Haphazard Electric Work

If you don't know what you're doing, it's probably best to call a pro for assistance with automotive wiring.

You wouldn't tackle a wiring project in your house without turning off the power at the source and then double-checking at the site of the problem, right? (Well, let's hope you wouldn't, anyway.) Same thing with your car. A little laziness might get you zapped.

Some automotive pros say that the current in your car isn't strong enough to really hurt you but it's always better to be on the safe side, which means assuming that you could sustain injury . Even if you don't suffer an electrical shock, you could easily start an electrical fire, or possibly overload your car's wiring or other electrical components. So, you should know what you're dealing with ahead of time. Make sure your car is off when it needs to be off (which would be most of the time) and remember to disconnect (and then isolate) the battery's negative cable. And if you drive a hybrid car with a high-voltage battery, avoid touching the battery at all costs. Since hybrids are designed specifically for heavy-duty electrical power, the battery has much more shock potential than an average car and can cause injury on contact.

No.4 Assuming Bald Tires will last a bit Longer

Even if the tread looks decent, rubber deteriorates over time.

It's always tempting to try to squeeze a few more miles out of your rubber, but it's certainly not wise. You need to give your car what it needs to maintain proper contact with the road. Think of all you ask your car to do for you, every single day. Now imagine picking up the kids from school in a snowstorm wearing flip-flops, or taking the dog for a run while wearing stilettos. It's all wrong. Your feet need better equipment to get the job done. So does your car.

If you don't know how old your car's tires are (you bought your car secondhand, or you're not a meticulous receipt- or record-keeper) chances are you're probably due for a new set. Even if the tread looks decent, rubber deteriorates over time. The damage might not be easy to see, but miniscule cracks cause loss of structural rigidity, which means the tire can't perform as designed. If the rubber disintegrates where the tread joins the tire, the tread can separate (yup, just like a semi-truck). Not really worth taking the chance, is it?

No.5 Sloppy Lube Job During Brake Repair

If axle grease or caliper lube gets on the friction surface of the brake pads or rotors, your car's brakes won't work.

Even though brake jobs typically aren't (strictly speaking) all that difficult, a lot of amateur mechanics like to hire a pro for this kind of work. And it's understandable. Screwing up a brake job can have pretty serious consequences, for obvious reasons. Your car's brakes work because of friction. It's not entirely that simple, but that's the basic principle. When you press (or slam) the brakes, hydraulic pressure in the system makes your brake calipers and brake pads squeeze in, and this friction causes your wheels to slow down.

That's a lot of friction, and it depends on a lot of moving parts. Moving parts require lube, or else they'll seize. So when you're taking brake components apart and putting them back together, you'll need to use brake-system-specific grease to make sure everything's operating at top-notch capacity. And if you're working with the axles, there's a strong chance you'll be using oily substances in the brake vicinity. Either way, you'll want to be extremely careful with lube application -- it's crucial. It requires the precision of carving a really expensive steak, or giving someone a tattoo. If axle grease or caliper lube gets on the friction surface of the brake pads or rotors, your car's brakes won't work. Not at all.

No.6 Forgetting to Torque the Lug Nuts

A pile of lug nuts at the Charlotte Motor Speedway in Concord, N.C.

Even though Popular Mechanics has this handy tutorial that explains how to achieve the proper amount of force for lug nuts, don't let that intimidate you. If you managed to change out a wheel (or rotate all four corners) without dumping the car off the jack, you should be able to handle simple lug nut installation. Just read your owner's manual for the proper specs and use a torque wrench. That's what they're made for.

But apparently, plenty of people can't seem to get this right. So, after going through all the effort of moving the wheels around for a tire rotation or replacement, they scurry off with the wheels insufficiently bolted on. Guess what -- they won't be on for long. Note also the very real possibility of over-tightening the lug nuts -- it may be a little less obvious than under-tightening, but it has similar consequences. Instead of a loose wheel simply wobbling until it works its way off, all the tension of driving compounds to further stress out the over-tense lugs. Improper amounts of metal-on-metal friction ensue, and over time, something's gotta give. The lug nut or the wheel stud, being the smallest parts of the equation (and likely damaged by over tightening), may eventually snap-off. Not good.

No.7 Forgetting to Replace Drained Fluids

It's a good idea to double-check (or even triple-check) that you replaced whatever fluid you drained out of your car.

Fluids have a lot of purpose in a car -- and believe it or not, most of them are equally as important as gasoline. True, without fuel, you're not going anywhere ... but that's probably the worst that'll happen (assuming you're out of harm's way when you actually start to sputter out). Your car's other liquids actually bear a heavy burden, too. Maybe even heavier than the expensive stuff you burn to keep going.

You always need oil -- if your engine's moving parts go dry, they'll seize up for good. Same with the transmission fluid. Brake fluid helps maintain proper pressure within the braking system. 

And your car's coolant (aka antifreeze) keeps things from getting too hot or too cold -- running out of any of these fluids can be disastrous.And everyone's heard horror stories about a minimum-wage tech at the local outpost of the national lube chain who forgot to refill the oil after a change, right? Well, those things happen. It can happen to the so-called pros and it can happen to you, too. So if you're DIY-ing it up in your garage, double- and then triple-check that you replaced whatever liquids you drained. It doesn't hurt to check after your mechanic's done, either. If you screw that up, it won't matter that you're always out of windshield washer fluid.

No.8 Forgetting to Tighten the Oil Filter

You should be able to install your oil filter by hand; however, once the filter is hand-tight you'll need the wrench to crank it down the final half-turn.

It comes right on the heels of similar advice, but still, we can't emphasize this enough: If your engine isn't circulating the proper amount of oil, it won't be long before you're calling for a tow truck.

Mike Allen, of Popular Mechanics, says it's important to have the right size wrench to remove and replace your oil filter -- if the wrench wraps around the canister too loosely, it might feel like you're cranking hard without actually making any progress. If you switch filter types, your old wrench might not work anymore. Make sure you check the fit before you leave the parts counter.

You should be able to install your oil filter by hand; however, once the filter is hand-tight you'll need the wrench to crank it down the final half-turn. It's really important to make sure you do that last part. A loose filter will soon send your engine's oil spewing everywhere. In that case, yes, your engine could seize; but it's more likely that a fire under the hood will put an end to your drive before that happens.

No. 9 Ignoring Warning Lights

It's pretty easy to get desensitized to those dashboard warning lights.

Warning lights are kind of like the little boy who cried wolf -- you know you need an oil change, but that check engine light comes on all the time, right? The sad truth is this: It's pretty easy to get desensitized to those dashboard warning lights. A lot of the time, there's really nothing wrong ... or at least, you think you know what's wrong and you'll get around to it -- eventually. There's nothing wrong with getting to know your car this way. In fact, it's good. But when your car is trying to tell you something, you really should listen, even if you'd really rather not hear what its saying. And that's exactly what warning lights are for. Conundrum!

At the very least, you should know what all the warning indicators mean -- if one comes on and it's not familiar to you, look it up in your owner's manual. If it's something you can easily fix yourself (low tire pressure would be a good example), go do it. Sooner is better than later. See? You fixed it! How satisfying! And if a warning light indicates something more complicated is going on, it's a good idea to have your car looked at by a professional. Becoming immune to your car's cries for help might be less expensive in the short run, but definitely not in the long run.

No.10 Flouting Safety Recalls

If your car is ever part of a safety recall, the manufacturer (or the dealership) will attempt to contact you by mail.

Sometimes safety recalls happen because an automaker finds a problem. Sometimes a recall is ordered by the National Highway Traffic Safety Administration (NHTSA), which keeps detailed records of consumer automotive complaints. The recalls might be major safety concerns -- like exploding tires or self-accelerating gas pedals. Others might seem superficial in comparison -- peeling clear coat on your wheels isn't pretty, but it won't lead to your imminent demise.

Major recalls usually make the news. Your car's manufacturer or the dealership will probably try to contact you by mail. You can also look online, or call your dealership -- which is especially useful if you bought a used car because the dealership can run your car's VIN to see if there are any other outstanding recalls on that make and model year. And if you ever have to pay for the dealership to fix a safety issue that isn't already part of a recall, save your paperwork -- if your car is recalled in the future for related issues, you might be eligible for reimbursement. Occasionally, someone else is willing to take responsibility for your car -- don't squander such a rare opportunity.