HomeTowne Auto Repair and Tire Blog

What causes a check engine light to turn on?

In Automotive Diagnostics by HomeTowne Auto Repair & TireOctober 22, 2020

Updated April 18, 2024

During your daily travels or on extended trips, you may have noticed your car’s check engine light turn on.

This symbol isn’t one that should be ignored for long. When it appears on the dashboard, it’s cluing you in that there’s a problem. What that issue is exactly … well, that mystery can take some time to solve. The root cause could span a number of components and various systems.

Every vehicle is made up of a different set of monitors. Some examples include fuel monitors, EVAP monitors, and catalyst monitors.

The car is constantly testing itself, with several tests performed at one time. Each test has a certain parameter, and a code is sent if something is wrong.

Flashing check engine light

Before we delve into the possible culprits behind a check engine light, we want to point out that you should avoid driving a vehicle if the icon is blinking.

If you’re driving when this occurs, pull over to a safe location and have it towed to a mechanic or auto repair shop you trust. Continuing to drive the car when the light is blinking can lead to catalytic converter damage.

A lot of times, a flashing check engine light may indicate a large misfire. You could have a bad spark plug or ignition coil. It’s also possible that a fuel injector is failing or the driver inside the computer isn’t sending the signal to that cylinder.

It’s OK to use the car if the light remains solid, but we recommend getting it looked at as soon as possible. Bringing the vehicle in sooner rather than later allows the automotive expert to address any major problems. This also makes it easier for them to figure out the initial code (and helps up the diagnostic testing process).

Check engine light causes

Numerous problems can lie behind a check engine light.

Maybe the spark plugs or ignition coils are going bad, or there’s a malfunctioning sensor. You might have a loose gas cap that needs to be tightened. Being low on oil is another possibility.

The could be a sign that the catalytic converter isn’t working right. This was the case with a Dodge Caravan we worked on.

Problems with the circuit system, catalyst system and coolant system are also reasons why the symbol appears.

A misfiring engine is a more serious issue that the icon would point out.

Here are other potential check engine light causes:

Problems with the transmission
Oxygen sensors
Evaporative system issues
Anti-lock braking system (ABS) problems
Wrong oil

Other symptoms to watch for

If you see the check engine light turn on, make sure to note when it appeared. We also recommend that you keep an eye (or ear) out for other symptoms.

Does the vehicle feel like it’s running rough? Do you hear any noises? Did any other dashboard lights come on?

The sounds and behaviors you notice can vary. So, just be aware of anything out of the ordinary.

Some of your observations might not seem important. However, sharing these details with an automotive professional can narrow down their search as they track down what’s causing your check engine light problem.

HomeTowne Auto Repair & Tire is an authorized Michelin and BFGoodrich tire dealer located near Lake Ridge, Virginia. Automotive repair services are performed on all makes and models, including oil changes, brakes, alignments, inspections, and computer engine diagnostics.

View Post

Why you should change your cabin air filter and clean the cowling

In Cabin Air Filter by HomeTowne Auto Repair & TireOctober 13, 2020

Leaves will soon begin falling across Virginia.

They can become lodged in your car’s cabin air filter or the cowling area.

Cabin air filters clean the air that goes into the front of vehicles and prevent bacteria, dirt, dust and pollen from entering.

They keep the heating core and evaporator from getting blocked, as well.

Once or twice a year, it’s a good idea to clean out and vacuum the cowling area, where leaves, sticks and pine needles can build up.

Leaves and pine needs in a car's cowling area. — Once or twice a year, it’s a good idea to clean out and vacuum the cowling area, where leaves, sticks and pine needles can build up.

The windshield wipers hook up at the cowling area and water from the windshield drains into it before running off the sides under the car.

It also houses the windshield wiper motor and air intake for the heating and air conditioning system and cabin air filter.

Why you should clean the cowling area

Cleaning the cowling area can help keep your cabin air filter clean and prevents your car from smelling moldy.

It’s important to have the cabin air filter replaced regularly. If it isn’t, it becomes more clogged and may add more stress to the blower motor.

In addition to leaves, cabin air filters may become home to animals that are seeking warmth or shelter.

One indicator that your cabin air filter isn’t working properly or it’s blocked by too many leaves or a mouse nest, is that particles will come out of the vent when you turn the air conditioning or heat on the highest setting.

Cabin air filters should get changed every 10,000 to 20,000 miles, depending on the car’s make and model and where it’s driven.

A vehicle that travels down a dirt road every day may need to be replaced more often than one that goes from a driveway to the interstate.

Our technicians check cabin air filters during oil changes, as part of our courtesy inspection. They also spray the disinfectant BG Frigi Fresh into the air intake system.

Cabin air filter types

So, what kind of cabin air filter should you use?

It’s like getting an air filter for your house – you can buy a $3 air filter or $30 air filter.

Depending on the make model of the vehicle, you can spend $3 to 5 or up to $75 or $80 for a cabin air filter.

How the air filter is made, if it will get distorted, and the materials the filter is made out of also impact the price.

On some vehicles, like BMWs and Mercedes, they may have a charcoal filter built into them, which are going to be more expensive. Some vehicles have two cabin air filters, others have none.

HomeTowne Auto Repair & Tire is an authorized Michelin and BFGoodrich tire dealer located in Woodbridge, Virginia. Automotive repair services are performed on all makes and models, including oil changes, brakes, alignments, inspections, and computer engine diagnostics.

View Post

Tell your auto repair shop everything

In Vehicle Alignment by HomeTowne Auto Repair & TireOctober 8, 2020

Details are key.

When dropping off your vehicle at an auto repair shop, it’s important to provide as much information as possible – whether it’s a noise you hear, work that has been done, or a recent incident.

The driver of a Dodge Avenger brought their car in for a wheel alignment and explained that they had hit a curb.

Before performing alignments, our technicians complete a free courtesy inspection. During courtesy checks, they check various components, including the brakes and lights.

When looking over the Dodge Avenger, we noticed that a wheel and tire were damaged and that the wheel would shift back and forth when the brakes were applied. The lower control arm was broken, as well.

Lower control arms are responsible for linking the frame with the suspension.

As one of the technicians removed the broken lower control arm, he saw that the subframe was bent and needed to be replaced.

How sharing information with an auto repair shop helps

Providing details to your mechanic gives them an idea of things they should be watchful for and steps they need to take to care of your car.

It can also prevent more damage from occurring.

View Post

Headlights: What’s checked during the Virginia Safety Inspection

In Car Safety by HomeTowne Auto Repair & TireSeptember 29, 2020

Updated July 10, 2025

How are your car’s headlights holding up?

Whether it’s a longer evening in the fall or a rainy spring day, it’s important that drivers have functioning lights.

Since many of us don’t turn on our headlights until we’re in the vehicle, we don’t always realize when they aren’t working correctly.

It’s also easy to miss minor problems unless you’re taking a closer look.

Headlight checks are a part of the courtesy inspections we perform when servicing a car. They’re also included in the annual Virginia Safety Inspection.

Headlight problems that inspectors look for

We keep an eye out for several headlight problems when conducting a Virginia State Inspection.

When bringing a vehicle into the shop, our technicians confirm all of the lights are working, including the high beams.

We look for headlights that are too dim or too bright, as well. The candlepower and aiming can be determined using a headlight aligner machine.

Mercedes headlight bulb not sitting right. — Mercedes headlight bulb not sitting right

It’s also important that the headlight assembly is secure and mounted correctly. If the assembly is shifting, the vehicle will fail the Virginia Safety Inspection.

Inspectors want to check for any cracks in the lenses, which can alter the aiming pattern. Why do we focus on this? When you’re stopped at a traffic light or traveling down the highway, the headlights must be aligned in a certain way so you don’t blind oncoming traffic.

If a headlight is pointed up or to the left too much, it could impair the vision of other drivers and cause an accident.

The lens color is looked at, too. The headlights and back up lights must be clear. Meanwhile, brake lights should be red and turn signals need to have amber bulbs.

Foggy headlights are another problem our technicians are watchful of. Overtime, the clear coating on the lights wears off. The issue can be resolved through headlight restoration or replacement.

Replacing headlights

In a lot of cases, a car just needs a new bulb. However, there are instances when changing the entire assembly is the way to go.

Damaged and hazy lenses are a couple of reasons why headlight replacement may be recommended.

Old and new headlight. — Old and new headlight

Sometimes, wiring problems are discovered during an inspection or maintenance service. Poor contacts with the connector is one example. There is so much heat that the ground connection can melt the connector. A blown fuse is another possibility.

We have suggested new headlight assemblies after finding condensation in them because they don’t come apart. In certain cases, a new assembly is needed when the bulb goes bad.

The lifespan of a headlight depends on the quality, as well as how often and where the vehicle is driven.

If you choose to replace yours, verify that it’s approved by the SAE with the correct number. This will determine if the headlight can be used on the road.

Cheap headlights that fit your vehicle are available for purchase online; however, they might not be allowed for highway use. If not, you could get a ticket. Headlights that aren’t SAE approved also won’t pass the Virginia Safety Inspection.

View Post

Signs your water pump is going bad

In Vehicle Fluids, Vehicle Maintenance by HomeTowne Auto Repair & TireSeptember 25, 2020

Updated February 21, 2025

Is your car’s coolant level lower than it should be? Have you seen a red thermometer symbol (the engine temperature warning light) appear on the dashboard?

There could be something wrong with the cooling system. When working properly, this system keeps the engine from overheating.

Parts can wear out from daily use, and coolant leaks may develop in a variety of spots.

The water pump is one component that might eventually need to be replaced. This item sends coolant through the radiator.

If the pump is going bad, it can mean that coolant isn’t moving through the engine or fluid is being lost. There’s also a pulley and a bearing where if the pump starts wobbling it can throw the belt and may damage other parts.

Symptoms and causes of a bad water pump

Water pump replacement may be needed if the part is corroding or loose. An automotive technician may notice these problems when looking over your vehicle.

Leaking water pump on a Jeep Grand Cherokee. — Leaking water pump on a Jeep Grand Cherokee

Sometimes, you might notice certain indicators when you have a bad water pump, such as an overheating engine. Coolant could also be seen leaking in the center of a vehicle’s front end.

If the engine does run warm, steam might be released through the radiator cap.

You might hear rattling and squeaking sounds, as well. The rattling noise would come from the bearing. Meanwhile, movement of the pulley may result in a squeaking.

Different water pump problems are possible. This part may go bad if a bearing wears out or there’s a bad seal or gasket. Cracks could develop in the water pump, too.

Those who are having water pump problems and technicians who are looking into these issues: You can read some recommendations in this article we wrote.

Installing a new pump on a Cadillac

One of our technicians installed a new pump on a Cadillac, which was overheating and had a coolant leak.

As the technician worked on it, he noticed that the drive belt and drive pulley had been shredded. We think this was caused by the pump locking up.

Shredded drive belt and drive pulley on a Cadillac. — Shredded drive belt and drive pulley on a Cadillac

To access it, the technician needed to remove the water pump housing, which includes part of the EGR system and Evaporative Emission Control System (EVAP system).

For some cars, water pumps are timing belt driven, meaning that the front cover of the engine needs to come off. This part is primarily timing chain driven on Fords, so the chain needs to be removed.

A majority of vehicles have pumps on the outside of the motor on the accessory belt drive. Most front-wheel drive cars will have them on the passenger side. On rear-wheel drive vehicles, the pump is usually in the center near the radiator.

Taking care of your water pump

The lifespan of water pumps depends on the vehicle. We’ve seen them last as long as 300,000 miles or make it to 50,000 miles.

Maintaining the cooling system can help you get the most out of this component and other parts. By performing regular coolant fluid exchanges, you are replacing fluid that would eventually turn acidic.

We also recommend making sure items are changed when they go bad, that the coolant remains at a good level, and the right kind of coolant is used on your vehicle.

View Post

BFGoodrich Advantage T/A Sport Tire: A high quality, all-season tire

In Tires & Wheels by HomeTowne Auto Repair & TireSeptember 17, 2020

Are you in the market for a high quality tire with a lower price point?

The BFGoodrich Advantage T/A Sport Tire may be the right fit for your vehicle.

It is very similar to the Michelin Defender Tire, Michelin’s top tire. But don’t let that be the only reason that convinces you to consider this option.

An all-season tire, the BFGoodrich Advantage T/A Sport Tire offers quite a few benefits that make it a favorite among many drivers.

Improved traction and great grip

Traveling in the rain or snow can be challenging and a bit stressful. The BFGoodrich Advantage T/A Sport Tire is a great choice to have on your side in these conditions.

Made up of locking 3-D Active Sipe Technology, it gives you improved traction that is especially helpful when you’re driving through wet or snowy weather. Its siping helps push away water.

The tire’s excellent grip is another perk that can’t be ignored. This grip, which is possible because of silica-infused compounds, can be counted on all year long.

BFGoodrich Advantage T/A Sport Tire: Reliable and comfortable

You don’t just want a tire that can be trusted in inclement weather. It’s also important that the one you choose for your vehicle is reliable when going around corners or traveling at higher speeds. (If you live or work in Northern Virginia, you know that high speeds are a norm on major roads and highways.)

Not only does this BFGoodrich option meet those needs, it does so while also providing a comfortable ride. This can be attributed to its sidewall stabilizer. Having that trait in a tire can help make longer trips more pleasant.

A quiet ride that’s long lasting

The last thing you want to hear while commuting or running errands is a noisy tire. That’s one problem you don’t need to be concerned about when using the BFGoodrich Advantage T/A Sport Tire.

And this quiet ride is one you can enjoy for many miles, as it is backed by a 60,000 to 70,000 mile tread life.

Both of these qualities are the result of Computer Optimized Footprint.

How well this tire steers is another benefit that fans have noticed. The steering response is consistent, due to the Continuous Center Rib.

The BFGoodrich Advantage T/A Sport Tire is one that drivers shouldn’t be so quick to dismiss.

Sizes are available for different types of vehicles, including trucks, SUVs and smaller cars.

HomeTowne Auto Repair & Tire has a wide selection of tires. We also offer a nationwide road hazard warranty for all tires that we sell.

To learn more about this BFGoodrich tire or any other tires, feel free to reach out to us. One of our staff members would be happy to help you determine the best tire for your vehicle.

View Post

Car windows on Subaru wouldn’t roll down

In Uncategorized by HomeTowne Auto Repair & TireSeptember 9, 2020

Are your car windows refusing to roll up or down? There are a few different causes behind this.

A Subaru driver dropped off their vehicle at HomeTowne after realizing the passenger car windows weren’t working.

First, the technician checked the window switches. He then moved on to the motors for the passenger windows and learned they weren’t working.

Located in the car door, the window motor is one part that is needed to open and close the window.

When you press the switch, a current goes to the motor. This starts the regulator, which causes the window to go up and down.

For some vehicles, the motor and regulator can be ordered separately. In this case, they came as one assembly.

Window Motor and Regulation Assembly. — Window Motor and Regulation Assembly

What can cause problems with car windows?

The motor going bad is one car window problem that can occur. It could also be installed incorrectly.

A window with automatic up and down may not roll down if a car battery has been changed or disconnected. Some drivers believe that the window is broken, when it just needs to be reprogrammed.

This issue can also happen with sunroofs.

The window switch is another part that can stop working.

If your window isn’t opening or closing, it’s also a good idea to make sure the window lock button hasn’t been pressed.

View Post

Emission test required every two years

In Vehicle Maintenance by HomeTowne Auto Repair & TireSeptember 1, 2020

Every two years, Northern Virginia drivers must have an emission test conducted on their vehicle.

This requirement applies to those who keep their cars in certain localities, such as Prince William County and the cities of Manassas and Manassas Park.

The emission test seeks to protect the environment by making sure the car releases the right amount of fumes into the air.

It is run by the Department of Environmental Quality (DEQ).

HomeTowne Auto Repair & Tire is an emissions shop. It became a Virginia Certified Emissions Repair Facility in 2017.

What happens during an emission test?

We confirm details about the car, including its weight and Vehicle Identification Number (VIN).

When testing a vehicle that’s older than 1996, inspectors use a sniffer tool that’s put inside the tailpipe. They also check for various components, including the catalytic converter, O2 sensors and the Evaporative Emission Control System (EVAP).

We use an OBD II connection device on newer cars. The DEQ computer plugs into the OBD II port on the car and checks for problem codes and system monitors.

Those monitors can include the EVAP system, catalyst (catalytic converter), 02 sensors, the EGR system, Oxygen Sensor Heater and secondary air system.

What can cause you to be rejected for testing?

There are a few ways you can be rejected for getting an emission test: if there are bald tires, an audible exhaust leak, or fluid that’s dripping on the dyno machine.

Why does that matter?

We have to make sure the vehicle is safe to run on the dyno, in case the DEQ requires it.

View Post

What impacts oil change prices?

In Oil Change by HomeTowne Auto Repair & TireAugust 26, 2020

As the due date for their next oil change draws closer, a lot of drivers wonder how much it will cost them.

A few factors can have an impact on the bill.

Oil change prices can depend on how many quarts a vehicle has and the type of oil it needs.

The make and model of a car also play a role.

For example, oil change prices may be more for BMWs, Mercedes, or other luxury vehicles because they require special scan tools to reset the maintenance lights.

Mercedes and BMWs have several lights that can be triggered, so it’s important for technicians to take their time and check them off.

When and why to change your oil

The manufacturers of some cars, like the Mercedes-Benz built after 2010, suggest changing the oil and oil filter every 10,000 miles or after one year.

If you’re driving an older Mercedes-Benz, you may be better off changing your oil at the 5,000 mile mark.

TECHNICIAN TIP: One of our technicians wants to make sure he’s taking care of his Mercedes. He likes to change his oil at 5,000 miles and top off the fluid to keep everything clean in the engine. He also does that because the stop and go traffic in Northern Virginia can be pretty hard on a car.

Because there are so many different types of oil out there, it’s hard to stock every single one. At HomeTowne Auto Repair & Tire, we use synthetic oil so every car gets the best oil. Read about our switch to full synthetic.

Therefore, with all of the commuting, we recommend a 5,000 mile interval with our oil, as that’s also a good time to rotate the tires.

Our technicians rotate the tires and perform a courtesy check during every oil change.

If you don’t change your oil or if you go too long without an oil change, it can cause damage to the engine. Running on too little oil prevents the oil from getting to components it needs to.

Regular oil changes keeps your engine working properly. They also help prevent sludge buildup.

Checking your oil

We recommend checking your oil every other time to fill up on gas.

If you notice you’re low on oil, it’s OK to add oil between oil changes as long as it’s the right type, viscosity and amount.

However, it’s important to keep an eye on it, because a vehicle shouldn’t use or lose oil. If you’re losing more than a quart or two between oil changes, it could mean that there’s a leak or the oil is being consumed internally.

Depending on the type of engine you have, the valve can go bad on the intake manifold. That can lead to an oil consumption problem.

View Post

Five possible reasons why your air conditioning isn’t working

In Automotive Diagnostics by HomeTowne Auto Repair & TireAugust 19, 2020

When the sun is beating down during your commute or on long car rides, it’s nice to have an air conditioning system that works correctly.

In the spring and summer, many drivers will notice that the AC won’t do its job. There isn’t one set answer for this issue. A number of problems can prevent cold air from flowing through the vents.

Below are five potential causes of a/c problems.

Some air conditioning issues

Low on freon: One possibility is that the car could be low on refrigerant. This means that the system likely has a leak. Air conditioning leaks could be coming from multiple locations, including fittings, rubber gaskets, and lines.

Low pressure line between the condenser and compressor leaking. — Refrigerant leak on Nissan Altima

Malfunctioning expansion valve: It’s also possible that the problem lies with the expansion valve, which helps control the amount of freon that flows through the A/C system. This component may not be working correctly.

Electronic Climate Control System: Another part that could be failing is the Electronic Climate Control System. This function determines how cold or hot it gets in the front of the car.

An electronic climate control system. — Electronic Climate Control System

Operator error: Today, the setup for A/C systems varies among vehicles. So, it’s very easy to hit the wrong button — or not the one you should. It’s a good idea to read the owner’s manual and make sure you aren’t missing something.

Turning on the air conditioning. — Turning on the air conditioning

Constricted air conditioning condenser: You might also want to check to see if the condenser is constricted. Due to improper cleaning or an impact, the fins could become bent and block the airflow.

Old air conditioning condenser. — Old air conditioning condenser

Testing the a/c system

The reasons mentioned above are just a few potential culprits behind air conditioning problems.

As we mentioned, an a/c system might not be working due to a leak. Because leaks aren’t always visible and can occur in different areas, we need to narrow down the search. To do this, we take a look at how the system is running.

With a machine, our automotive technicians determine the amount of refrigerant it has. Through vacuuming, they can see if leaks are present. Ultraviolet dye and oil are injected into the system to determine the location of the leak. The car AC is recharged after this process.

How soon we can see the ultraviolet dye varies. Sometimes, a vehicle needs to be driven 100 miles or so and brought back to the shop before we can find the leak.

Drivers don’t need to wait until they’re experiencing a problem. However, it’s important that they avoid waiting too long before having the system checked again. The dye can get all over the place or wash off.

Bringing your car in for a/c repair

When bringing your vehicle in for a/c repair, provide as many details about the problem as possible.

Some important information includes what you noticed, when you noticed it, and what has happened since then.

You may be asked if you have good airflow through the vents, if you can change the temperature control, or if an event occurred around the time that you started experiencing the problem.

These answers and additional details allow us to focus on certain areas or issues.

Page 14 of 25
←
1
...
13
14
15
...
25
→