Changing Headlight Bulbs
Novice mechanics can change their headlight bulbs but accessing the bulbs can be complicated. Once you've opened the hood, see if the three-wire plug at the back of the headlight assembly is visible. If not, you'll have to jack up that side of the vehicle, remove the wheel, and see what's necessary to loosen the fender panel. (The panel is held in place with fasteners that are unique to each car model.)
Once you can reach the headlight plug, remove it by unfastening the clip, screw cap, or plastic catch that holds it in place, and pull out the bulb. After you pull out the bad bulb, be sure to hold the replacement bulb by its plastic housing. Don't touch the glass, not even with latex gloves.
Replacing the Thermostat
If your engine is overheating or is slow to warm up, your thermostat could be either stuck shut or stuck open. Replacing the thermostat can be a straightforward job that won't require draining all of the engine coolant.
In the vast majority of cars, you'll find the thermostat where the top radiator hose goes into the engine. Look for two or three bolts holding the thermostat housing in place beside the entry point. Before detaching the radiator hose so you can put a wrench on the bolts, place a pan or bucket below the engine—you're likely to spill some coolant. After unbolting the old thermostat, check to ensure that the replacement gasket is a perfect match for the old one. One more thing: On some of the older cars you could put the thermostat in upside down. Nowadays, most of them have designs that prevent them from going in upside-down.
Replacing the EGR Valve
That Check Engine light might also come on if you have a faulty exhaust-gas-recirculation (EGR) valve. EGR valves are pollution-control devices that reduce nitrogen-oxide emissions by sending a little exhaust gas into the intake manifold. If your EGR valve is faulty, you'll notice rough idling, engine knocking, poor fuel consumption, overheating, or even a failed emissions test. Once you've found the EGR valve (usually at the back of the engine bay on the driver's side), disconnect the electrical and vacuum lines leading into it and unscrew the valve with a socket wrench. That's all you have to do before installing the replacement valve.
Fixing a Leaky Sunroof
If your sunroof is leaking for reasons other than a crack in the glass, the problem is probably plugged drain holes. Open up the sunroof and clean any debris in the tracks. Then find the drains, which are usually in the corners. If you don't have an air compressor and a "wand" for the air-compressor hose, you might try going to your local convenience store and using their compressed air to shoot blasts into the drains to clear them. You could also try unclogging the drains with a section of wire coat hanger. Just be gentle when you push the wire into the drain line.
Replacing Front Antiroll-Bar Bushings
If you hear or feel some thumping around your feet as you drive your vehicle, the source could be worn-out bushings on either side of the front antiroll bar. Replacing those bushings is not always easy or straightforward because, among other hurdles, there could be chassis components blocking them. But if the bushings are easily accessible, the job is doable for a weekend DIYer.
First, secure the front of the car on jack stands. Then locate the sway bar, which spans the width of the chassis and links the front suspension assemblies. Replacing the bushings is as simple as unfastening each of the single bolts that attach the sway bar to the lower suspension arms. Note: If you've been hearing a squeak instead of a knocking, it's probably the ball joints, and replacing those is definitely not for novices.
Changing the Automatic-Transmission Filter
The fluid in your automatic transmission will degrade significantly if it's exposed to very high operating temperatures. To be absolutely sure your automatic transmission is properly lubricated, the fluid should be changed at the intervals specified in the manual (usually every 15,000 to 30,000 miles).
If you decide to follow that maintenance schedule, you should also change the transmission filter. Secure the car on four jack stands, empty the fluid through the drain plug (if your car has one), then unbolt the pan. If you don't have a plug you'll need to slowly remove the bolts, leaving the forward-most bolts attached, but loose, so the pan can tilt down to drain (and you'll want a large drip pan). Once it's off, the filter is easily seen and replaced. After reattaching the pan, refill the transmission through the dipstick tube, which you'll find in the engine bay. Use a long-nose funnel intended for transmissions, and pour in the recommended volume of fluid. Then start the engine, let it run until it reaches normal operating temperature, shift through the gears while stopped, and check the fluid level while in park. Add more fluid as needed, being careful not to overfill. And be sure you're using exactly the fluid grade specified in the owner's manual. Using the wrong fluid can seriously damage your transmission.
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