DIY Auto Tips

Brush up on basic vehicle skills to keep your car moving.

The good old days of automobile maintenance, when most repairs could be accomplished by anyone with basic mechanical skills and a few tools, are long gone. Modern vehicles rely heavily on computer technology and are much more complex and difficult to work on than their forerunners. Late-model vehicles are also vastly more reliable, so there’s less need to tinker. But every vehicle requires basic maintenance, and these tasks — and some emergency repairs — are DIY-accessible. Having the knowledge and tools available if something does go wrong can make the difference between a minor inconvenience and a major headache. The following tips provide basic guidelines for dealing safely with common maintenance jobs and repairs, but you should always refer to your vehicle’s owner’s manual for specific details.

Get Your Kit Together
In case you have to work on your vehicle on the road, you need a basic tool kit that’s small enough to store in the vehicle (photo, right). It should include a variety of Phillips, straight and Torx screwdrivers, a metric socket set and metric nut drivers (almost all late-model cars use metric fasteners), locking pliers, an adjustable wrench, an oil-filter wrench, electrical tape, duct tape (sometimes it’s all that’s needed to get you by), a flashlight and an emergency flasher, spare headlight and taillight bulbs, a car jack and a first-aid kit.

Get a Jump on It
If you need a jump-start, the correct sequence is important so you don’t destroy any electronics or shock yourself. It would be ideal for both batteries to be the same voltage, but this is not essential. First connect a jumper cable to the positive terminal of the discharged battery; then attach the other end to the positive terminal of the live battery. Next, connect a jumper cable to the negative terminal of the live battery and to the frame (such as a strut post) of the vehicle being jump-started. Be sure the cables are not in the way of any moving parts, such as belts and pulleys. Start the booster vehicle; then start the car being jumped. Once it starts, remove the negative cable first and then the positive cable. Leave the vehicle running to recharge the battery. Note: Driving the car will charge the battery faster than simply running it in park.

When jump starting, always connect the negative (black) cable clamp to the frame of the vehicle being started.

Keep Lights Shining
Oil and dirt will significantly shorten the life of halogen headlight bulbs. Handle the lamp with gloves or a soft paper towel, and wipe any dirt or grease off of the bulb. If access to the bulb is from the underside of the vehicle or if you need to remove parts other than the light housing, you may want to let a mechanic do the work. Note: You can spring for premium lamps that claim to throw a longer beam, but some tests done by consumer groups show there’s very little difference between brands in use.

Never touch the glass bulb of a replacement headlamp; the oil from your fingers will cause early failure.

(Don't) Jack It Up
The scissors jack that comes with most cars is meant for emergencies only. A hydraulic jack provides more security and is the preferred tool for any work in your garage. Be sure you always use a jack that’s rated for at least the weight of your vehicle. Put the transmission in park, and avoid working on an incline. Block both sides of the wheels that will remain on the ground to keep them from inadvertently moving.

When changing a tire, loosen the wheel nuts first before using the jack to raise the vehicle. Then raise the car until there’s about an inch of clearance beneath the tire. Remove the wheel and quickly replace it with the new wheel or spare. Tighten the wheel nuts by hand until they just start to snug-up the wheel; then lower the vehicle. Once the vehicle is back on the ground, gradually tighten the nuts in an alternating pattern across the wheel. (Refer to your owner’s manual for torque specifications.) Do not tighten the nuts in sequence by going in a circle; this can damage the wheel, particularly if it’s cast alloy. And do not lubricate the wheel nuts or studs, as that can cause them to loosen on their own.

Refer to you vehicle’s instruction manual for the correct jack location and how to use it safely.

It’s a good practice to drive the vehicle around the block after changing a tire and then check the nuts to make sure they are secure. Sometimes wheels aren’t aligned properly when you first tighten them, and they can loosen during driving.

Switch Batteries Safely
You’re not going anywhere if your battery dies. With most new vehicles, removing the battery means you could lose programmed information such as your radio-station settings, PIN codes or even engine-management information. (Battery-backup devices that plug into the accessory outlet can retain the programming.) If you install a battery incorrectly, you risk frying sensitive electronics. It pays to check your owner’s manual or the vehicle manufacturer’s Web site for tips before you start. Remember that battery acid is highly corrosive and can cause burns, and it produces a flammable gas — so no smoking! Also, remove any metal jewelry to avoid potential electrical sparking.

To help prevent short-circuiting, first disconnect the negative terminal and then the positive terminal. Remove the battery clamps or hold-downs and take out the old battery. Clean the cable clamps with a wire brush and a baking soda solution (about one tablespoon of baking soda and one cup of water). Install the new battery, reconnecting the positive terminal first. Apply lithium grease to the terminals to help prevent corrosion. You can recycle the old battery at any garage or car dealership, or you can take it to a metal-recycling business for some extra cash.

Change the Oil (and Filter)
Changing the oil is one job that hasn’t changed much (though most newer vehicles can go longer between oil changes than in the past). When you change oil, you should always replace the oil filter at the same time (see photo, below). The vehicle should be on a level surface and have a warm engine so the oil will drain more freely. First remove the oil-filler cap; then drain the oil by removing the drain plug on the bottom of the engine block. Use an oil-filter wrench to remove the old oil filter and clean the seating area before installing the new filter. (Apply a little motor oil to the filter seal first.) Replace the drain plug and pour in the new oil. Be sure to replace the cap. Run the engine for a few minutes to check for leaks. Turn off the engine and allow a few minutes to let the oil settle; then check the oil level to be sure it’s full. Recycle the old oil at an auto-parts store.

Many newer vehicles make changing oil more convenient by positioning the filter in an accessible spot.

Know How to Tow
Sometimes there’s no alternative to towing. This can happen as easily in your garage as out on the road, so it’s important to know the location of the tow points on your vehicle and how they should be used — always refer to the owner’s manual. Front-drive and rear-drive cars can be towed on their rear wheels with the parking brake released and the transmission in neutral (for rear-drive). All-wheel- and four-wheel-drive vehicles present greater challenges; the safest way to tow them is on a flatbed truck.

Know where the tow points on your vehicle are and if they require a special attachment, such as this screw-in tow hook.

This article is a revised version of "DIY Maintenance and Emergency Repairs," from the Fall 2014 issue of HANDY. The original version incorrectly showed how to jumpstart a vehicle.

Want more?
Learn how to detail your car like a pro.
Everything you need to know about windshield wipers.