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Reasons why the oil pressure light turns on

In Automotive Diagnostics by HomeTowne Auto Repair & Tire

Over the course of using a vehicle, you may occasionally notice a dashboard light illuminate. 

Many people are familiar with the check engine light, but there’s another one that you should be aware of – the oil pressure light.

This light can appear for a few reasons. If it does turn on, there are some immediate actions you should take.

Oil pressure light on? Here’s what you should do.

You should avoid using your vehicle if your oil pressure warning light turns on. What if it appears when you’re driving? Pull over in a safe location. 

The oil level on an oil dipstick.

Then, check your oil. To learn how to do that, check out our “How to check your oil” article. If the oil level is good, don’t drive it and have it towed to a nearby auto repair shop. 

If the oil level is low, add oil and turn the vehicle on to see if the light goes out.  

What can cause the oil pressure warning the light to come on?

Low oil

Not having enough oil is one reason the light will illuminate. The oil pressure light is a lot of times going to be the same light that tells you that you’re low on oil. Low oil can be the result of an oil consumption problem or an oil leak. More information about the causes of oil leaks and the importance of addressing them can be found in this article we published.

Oil pressure switch on a Toyota Camry.

Bad switch

There’s a common problem with certain manufacturers where the oil pressure switch will just go bad. The switch is responsible for measuring the oil pressure and sending the signal to the dashboard. It’s possible that it may just need to be replaced.

Mechanical low oil pressure

Clogged ports and channels inside of the engine will cause low oil pressure. So, mechanically, low oil pressure will cause the light to come on. There’s a threshold. That car knows what the oil pressure should be at when idle, at wide open throttle, and at certain RPMs. The pressure is going to change. So, mechanically lower pressure than the specifications will cause the light to turn on.

How we address an oil pressure warning light

If a vehicle comes in with its oil pressure light on, we first start by correcting the oil level. It’s an easy, simple thing that a lot of people forget.

The second step is testing our switch and making sure it’s working. If it is, then we measure the mechanical oil pressure. We, basically, figure out what needs to be fixed.

Our findings will determine what the repair is going to be. The most common problem is sludge. Sludge buildup on these vehicles will lead to low oil pressure, because it blocks the passages. In that situation, we try to restore rather than repair.

Two GM engines we worked on had low oil pressure. One of the vehicles had mechanically low oil pressure and its low oil pressure light was on. We ran a cleaner through the engine and did some restore with transmission fluid. It cleared up the passages and the driver got his oil pressure back.

The other vehicle had a timing code that kept coming back from the variable valve timing system. A BG restoration kit was used, and the code never came back. This van always had good oil pressure, but it had a phaser that operated from oil pressure and was clogged.

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.

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Coolant leaking from Volkswagen Beetle

In Automotive Diagnostics, Vehicle Fluids by HomeTowne Auto Repair & Tire

This is the latest chronicle on the most recent car problem I had with my Volkswagen Beetle. I hope that my experience helps you address any issues you face.

I was taking my exit off I-95 South when I noticed what sounded like a rattling noise – and then turned into a grinding noise – as I stepped on the gas. 

I reached out to the General Manager at HomeTowne Auto Repair & Tire, thinking it was some sort of belt issue. 

However, as I spoke with him, I began to see other problems. Smoke was emitting from the front of my vehicle and I heard a loud beeping noise. That’s when I saw the engine temperature light and low oil pressure icons appear on the dashboard. This information was shared with the General Manager, who recommended I check my oil level.

The engine temperature warning light, which appeared on the dashboard of a Volkswagen.
Engine temperature warning light

I safely arrived home, where my fiance and I confirmed that there was oil in the system but saw that the coolant reservoir appeared empty. When he heard this, the General Manager suggested we add refrigerant to see if it had a fast leak. If it did, I would need to have the vehicle towed to their Woodbridge auto repair shop. Coolant was added and, sure enough, it leaked out immediately.

Why is coolant leaking from my car?

My Volkswagen Beetle was towed to HomeTowne Auto Repair the next morning. 

When it was brought into the shop, they found that one of the heater hose connectors had broken.

A broken heater hose connector.
Broken heater hose connector

What appeared to be smoke was actually steam. This occurred because the coolant was leaking directly onto the hot exhaust, which was burning it.

After replacing the connectors, one of the technicians topped the system off with coolant. However, when he turned the vehicle on coolant once again poured out.

Why was coolant leaking out of my vehicle?

Through a deeper investigation of the problem, they found that there was a crack in the oil filter housing. 

A crack that was found in a Volkswagen's oil filter housing.
Crack in oil filter housing

After replacing this part, a coolant system flush was performed to ensure that there weren’t any air pockets. My Volkswagen was then taken on a test drive to confirm that no other leaks were present.

A Volkswagen Beetle receiving a coolant fluid exchange.

Other possible causes behind coolant leaks

Coolant leaks are usually a matter of time and age. Rust, corrosion and impact are factors, as well.

They can be the result of many different components going bad. These include the water pump, radiator, heater core, thermostat, heater hoses, and radiator hoses. You also have multiple bypass hoses, depending on the car.

This article we wrote talks about some signs that you have a bad water pump.

Some high performance vehicles have two water pumps – a main one that’s belt or chain driven and there’s usually one that’s electric which supplements the cooling system. For hybrids, there’s a completely separate cooling system for the hybrid battery. Your hybrid vehicles will have their own water pump, hoses and thermostat.

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.

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Noises from the air conditioning system

In Automotive Diagnostics by HomeTowne Auto Repair & Tire

Whenever something is wrong with your vehicle, you may begin to hear strange sounds. The a/c is no different. Noises from the air conditioning system are one symptom you may notice when there is an issue.

What does a normal AC sound like?

When the ac compressor comes on, depending on the type of vehicle, you may hear a click and you might see the tachometer go down a little bit and back up as the engine is compensating for the load of the ac compressor. 

Weird noises from the air conditioning system

Now that we’ve covered what you should be hearing, let’s move on to those odd noises, and what’s causing them. 

Strange air conditioning sounds include:

  • Buzzing noises: If you notice a buzzing noise, it could be an ac compressor relay.
  • Clicking sounds: You should also keep an ear out for clicking sounds. A loud clicking is one indicator that the a/c compressor clutch is going bad. If it’s happening quickly, it could be that the system is low on Freon.
  • Clicking sounds inside the car: This noise may be due to actuators behind the dash that control the vent doors. Sometimes, the plastic pieces break or the motors go bad, and they will make a clicking noises.
  • Squealing noise: Squealing sounds are sometimes created if the a/c compressor clutch wears out. Other potential culprits include a bad pulley or pulley bearing, oil getting onto the clutch, or the compressor seizing up. The squealing could also be a loose a/c compressor belt.
  • Rattling sounds: The ac compressor or the compressor clutch going bad produce rattling sounds, at times. This noise – as well as knocking sounds and groaning noises – can also be heard if mounts are loose or broken. The drive belts becoming worn or damaged is another possibility. 
  • Rattling noise inside the vehicle: If you hear a rattling noise from within the car and you have kids or you put stuff up on the dashboard, we have found that paper clips and pens will fall down in the vents. Depending on how high you have the blower motor up, they might rattle around in there.  
  • Vibrating noises: An a/c hose rubbing against a component could lead to vibrating sounds. The blower motor going bad electrically or being unbalanced can create a vibration noise inside the car.
  • Swooshing sounds: As the ac system starts to build pressure, you may hear what sounds like water going through pipes or a swooshing noise. It usually has to do with the expansion valve or the orifice tube that the Freon is expanding through.

Other a/c problems

A leaking air conditioning condenser.
Leaking air conditioning condenser.

In addition to hearing noises from the air conditioning system, drivers may notice that it just isn’t working correctly. Maybe hot air is blowing out of the vents when the AC is turned on, or no air is coming out at all.

Air conditioning problems can be the result of several issues. A constricted air conditioning condenser and being low on freon are among the possible reasons why the a/c isn’t working.

Our Woodbridge mechanics can perform car ac repair services. This includes a/c diagnostics and electrical diagnostics, replacing parts, and tracking down any leaks. Check out this article we wrote to learn more about the a/c repair services we offer and what you can do to maintain this system. Conducting noise diagnostics is another service we offer.

An air conditioning condenser fan.
Air conditioning condenser fan.

If you are hearing any noises that are listed above or others that we didn’t mention – whether they are coming from the air conditioning or not – reach out to us. We can help you determine the problem.

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.

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Crank no start on Ford F-350

In Automotive Diagnostics by HomeTowne Auto Repair & Tire

A crank no start is a common problem that can occur with any vehicle.

It’s the reason that a customer brought their Ford F-350 to our shop earlier this month.

When looking into the problem, our technician found that the fuel injectors weren’t pressurizing. A high pressure oil system is used to pressurize the injectors, because they need 500 PSI just to fire. 

To determine the cause behind the pressurizing issue, he hooked up an air line to the oiling system and discovered a leak on the oil stand pipe. There was a broken o-ring, as well. When o-rings break, they will leak internally, resulting in a loss of pressure.

For this diesel, we needed to replace the oil stand pipe, which allows oil pressure to pump up the fuel injectors, and oil. They come as a set. The crank position sensor was also broken and a new one was installed.

The oil stand pipe for a Ford F-350 that had a crank no start. The oil stand pipe was replaced.
Oil stand pipe

Possible causes behind crank no start

A crank no start is a signal problem.

There are numerous possible causes behind this issue – so many that we wouldn’t be able to cover all of them in this article. 

Fuel delivery is the most common reason a vehicle won’t start, because if it’s cranking that means your battery has juice.

Most vehicles have a fuel pump in the tank, and then you will have a high pressure fuel pump under the hood. Either of those components could become clogged or broken. Some automobiles have in-line filters that may get clogged. A lot of newer vehicles have their filters in the fuel pump. You might also have a simple relay or fuse go bad.

Fuel injectors have tiny needles that go in and out. They could become clogged, preventing the needles from moving. Usually, however, injectors alone won’t prevent a car from starting. Instead, the vehicle will start but run poorly. 

The glow plugs, which are responsible for starting the engine on a diesel, could also be the culprit. They could have gone bad and need to be replaced.

Cam and crank sensors not functioning correctly is another possibility. This would be indicated by the vehicle’s inability to fire.

How determining the problem has changed

Years ago, vehicles had carburetors, rather than fuel injectors. Automotive technicians would follow the philosophy of “air, spark, fuel.” They would check those areas, and it didn’t get more complicated than that.

Now, it’s not so simple, because there are signals. Vehicles that are produced today have computers, parameters that need to be set, and security devices. Having so many more features at play can make the process of tracking down the problem a bit more difficult and time consuming.

Performing diagnostic testing on vehicles with a crank no start is one of the services we provide. If your vehicle is refusing to start, have it checked out by a car repair shop near you. 

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.

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How to tell if your car alternator is bad

In Automotive Diagnostics by HomeTowne Auto Repair & Tire

Are you having trouble starting your vehicle?

Your car alternator going bad could be the cause behind this problem.

Here are some bad alternator symptoms:

  • Battery light comes on
  • Grinding, growling and whirring noises
  • Electronics not working correctly
  • Dead or slow car battery
  • Burning electrical or rubber smell

More in-depth explanations of each indicator can be found below.

Signs of a bad car alternator

Battery light turns on: One of the first signs that you would see if your car alternator is going bad would be when the battery light comes on. It can be mistaken for a regular battery issue, but really it’s indicating that the battery isn’t being charged. Alternators are designed to take the load from the electrical system and charge the battery. Generally, you see 13 to 15 volts with an alternator. The battery light may turn on if it goes below that, or if it starts reaching 16 or 17 volts, which indicates an overcharging problem. Overcharging can cause many other problems in your vehicle. Depending on the electrical load – that can be anything from the air conditioning running, headlights, wiper blades, the radio, even the electrical doors like those found on minivans – can make the battery warning light flicker. That’s because the alternator is fluctuating and trying to compensate for the vehicle’s electrical load. If you start seeing that, it’s a good time to bring your car in for us to check the electrical system and, specifically, the alternator. That way you don’t end up on the side of the road.

Noises from under the hood: Hearing noises that are coming from underneath the hood is another common symptom to watch out for. Due to age and wear, the bearings on alternators can start to go bad. You may notice a grinding or growling noise. You can confirm that this is the problem if the alternator is on top by placing a screwdriver on the metal part of it and holding the screwdriver near your ear. If you hear the growling sound coming from there rather than another area, then that will tell you that the bearings are the culprit. Other noises can occur if the pulleys aren’t aligned correctly or the belt pulley bearings are worn, which can create grinding or growling noises and may sound as if it’s the alternator. Whirring is another bad alternator sound that will increase in frequency when you accelerate and decrease as you let off the gas. That is a sign that the alternator is trying to work really hard and is starting to go bad.

Electronics stop working or have delayed response: If your car alternator is going bad, the electronics on a vehicle may act haywire or work slower than normal. On some cars, you can see the dashboard behaving strangely  – the gauges may be moving back and forth, the lights might turn on and off. Newer vehicles have so many electronics. The alternator’s main job is making sure the car is safe to drive on the road. So, it could begin turning off electronics to ensure the engine and brakes continue to function. Really dim or bright headlights are another sign of a bad alternator. The headlights can appear dim if the component is undercharging or overcharging, the lights may get brighter as you hit the gas.

Dead battery or battery is slow to crank: Do you have a dead car battery, or has it taken longer to crank? You might not need a new battery. The problem could lie with the alternator. As you’re driving, the alternator is responsible for charging the battery. If it isn’t able to do that well, but it has enough juice to keep the electronics running the battery won’t be charged correctly and the next time you go to start the car you’re going to either have a slow crank or no crank. It may just “click” – as if you accidentally left your headlights on. You can jump start your car so you can head over to a car repair shop. But if you experience this problem, you should bring the vehicle in so a mechanic can check it out.

Burning smell: In extreme cases, drivers may notice something that smells like rubber or electrical wires are burning. The electronics inside the alternator or the bearings become hot and, next thing you know, you’re starting to cook the insulation on the wiring in the alternator. If it’s an electrical short, that’s where you get the wire burning smell. Basically, it’s an electrical fire. When the alternator is being overworked, it tries to push too much electricity through there and will melt items. If you notice this issue, you should stop and maybe even disconnect your car battery, because if there is an electrical short you don’t want any electricity running through there.

Drivers who experience any of these bad alternator signs should bring their vehicle to a nearby repair shop. The technicians at HomeTowne Auto Repair & Tire are able to check alternators, perform courtesy inspections, and conduct diagnostic testing. 

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.

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The role car computers play

In Automotive Diagnostics by HomeTowne Auto Repair & Tire

When you turn on your car, you’ll notice lots of lights on the dash and it may take a few moments before it stops looking like a Christmas tree.

The reason? There are many computers and modules that run various systems, such as the transmission and engine. Giving the car a minute allows these computers – called Electronic Control Units (ECUs) – to reset. Together, the ECUs form the Controller Area Network (CAN).

Sensors and modules send information to the computers and there are gateway modules that help direct traffic. So not only do you have sensors, you’ve got modules that actually control things, gateway modules that allow access, the CAN network, and the computer.  

Signs of computer problems and how we address them

If there’s a problem with a computer, the vehicle won’t work the way it should. You may notice a few issues. In addition to triggering the check engine light, a malfunctioning computer can impact the fuel economy and result in a no start.

Depending on what it is, there are driver information centers. It can be done through the dashboard lights or small computer screens that explain what’s going on or the system being affected.

Electronic problems can be difficult and time consuming to fix. Our technicians begin addressing the problem by performing a visual inspection. Then, we hook up the computer. We have special scan tools and we even have different ones depending on the type of car we’re working on. The scan tools at the auto parts stores may give you a code, but they don’t allow you to have full access. 

Reasons car computers fail

There are many possible culprits that can lead car computers to fail. It can be as simple as a sensor going bad and needing to be replaced.

Wiring can also become chafed. We’ve seen everything from too much being crammed under the seats, where a lot of modules are now located. In low end and high end vehicles, we have seen problems that have been the result of people spilling drinks or leaving the windows open. 

Sometimes, water leaks can occur due to windshield seals. The water goes in and it will corrode the connectors. You may not see it, so it could be difficult to diagnose because the water goes in, gets in the connector and starts to corrode it, causing an intermittent problem.

Water that collected in the well of a Mercedes, causing a module to corrode.
Water collected in the well of a Mercedes, causing a module to corrode.

In the case of one Mercedes, water soaked into the carpet and collected in the well, which was below the floor mat level. Overtime, this issue caused the module to corrode.

We’re finding water intrusion problems with all of the electronics in these cars – not just with the Mercedes. Even with the way the metals are sometimes made, you’re getting corrosion or connection problems, and that’s what’s leading components to fail. 

Some modules are underneath the vehicle or behind bumpers on panels. Even though they aren’t out in the elements, they see a lot of water and salt from the road. We’ve seen modules corrode on the outside and ruin the modules.

Shortage of car parts

With the parts shortages right now, where we used to be able to get just about any part within 2 to 4 days – even if it wasn’t as common – we’re starting to receive them in 2 to 4 weeks. 

For some of these older vehicles, we’re needing to rely on remanufacturers. You’re not able to get some new old stock from the dealer anymore. There’s even a shortage of used parts for some remanufacturers to rebuild them. So we may have to remove the part, send it off for repairs, and wait for them to send it back. That can take 3 to 6 weeks. 

With all that’s going on with the economy, it can delay vehicles getting fixed because we don’t have any other choice.

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.

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Car squeaking sounds and what causes them

In Automotive Diagnostics by HomeTowne Auto Repair & Tire

As you’re driving around town or on your way to work, you may notice a squeaking noise.

There are several reasons why car squeaking sounds occur. These are some of the most common causes:

  • Ball joints
  • Brakes
  • Control arm bushings
  • Sway bar bushings
  • Worn struts

Here is a more in-depth explanation behind the different components.

When ball joints create car squeaking sounds

Ball joints are a pivot point for the control arm, which supports the primary load of the car.

These components can create a squeaking sound when they run out of lubrication. They also may need to be replaced to resolve the noise.

Control arm bushings and sway bar bushings

Some control arm bushings and sway bar bushings make squeaking sounds if they need to be lubricated. Others have to be replaced. 

Whether you need new control arm or sway bar bushings or they need to be lubricated depends on how they come from a manufacturer.

Ball joint, lower control arm bushings, and new lower control arm.

Brakes

Brakes can make squeaking sounds if they are getting low. Most brake pads contain little metal tabs called “wear sensors” that can screech on the brake rotors. 

Brakes must be at or above 2/32 an inch to pass the Virginia state inspection. We recommend getting new brakes when they hit 3/32 or 4/32 of an inch, but some manufacturers suggest they be replaced sooner.

You can read more whether you need new brakes and the brake services we offer in this article we wrote recently.

Cheap brakes and those that haven’t been maintained properly can cause a friction noise.

We don’t suggest having cheap brakes installed, because they can cause noise, vibrations and rapid wear.

To learn more about why you shouldn’t use cheap brakes, check out this article.

Replacing only the brake pads and not the rotors may result in a squeaking sound.

Worn struts

Shocks and struts go bad overtime. The tires wearing unevenly and the handling feeling off are other indicators that these parts need to be replaced. These are some other signs.

We typically recommend replacing shocks and struts around 100,000 miles. However, if you’re getting new tires and your car is at 80,000 or 90,000 miles, we may suggest getting new ones earlier. This can help protect the next set tires.

How we address car squeaking sounds

To find the cause behind squeaking noises, we start by taking the car on a test drive. Then, we look for any problems by performing a visual and digital inspection.

After the inspection, our technicians recreate the issue. This allows us to isolate it.

Please make sure to provide the auto repair shop as much information as possible.

A customer recently had their vehicle towed for a brake check. The brakes were making noise, and he believed it was a caliper problem. 

When we touched the brakes during a test drive, they locked up and the truck slid. The customer didn’t mention that he recently had new brakes installed. Turns out, one of the calipers was missing. 

One of the more dangerous things you can do, as a customer, is not give us all of the information. When you don’t, it can be unsafe.

Having the whole story, including noises, problems you’ve noticed, and even a timeline, helps us solve the problem.

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.

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My car is making a clunking noise

In Automotive Diagnostics by HomeTowne Auto Repair & Tire

Are you hearing a clunking noise when you’re driving? Don’t worry, you’re not going crazy (well … hopefully not).

Clunking and rattling sounds are one sign you may notice when there is a problem with your car’s steering and suspension.

So, what’s the source of all that racket?

Well, the question of why a car is making a clunking noise isn’t an easy one to answer. Because many components make up this part of a vehicle, the direct cause might be hidden under layers of possibilities.

Possible causes of clunking noises

There are numerous reasons that could be behind a clunking sound.

It may be the result of parts – like strut mounts and bushings – wearing out overtime, due to age, wear and tear, driving conditions and driving style. 

Common causes of a clunking noise include sway bar links, which are small links and easier to damage. 

Sway bar end links and sway bar bushings are problems that are often misdiagnosed, because they sound worse than they are.

We worked on a Range Rover that had a clunking sound. When working on the vehicle, we found that not only had the ball joint come out of the steering knuckle, but the sway bar end link was broken.

Struts have mounts on the top that can make a knocking sound. The spring typically lasts the lifetime of the vehicle, depending on what model you have. Normally, the strut inside won’t make any noise. Bearings located on the strut mount, however, could make a knocking noise when they wear out. 

The issue might also have to do with the drag link, control arms or coil springs. Other culprits of clunking noises are: idler arms, pitman arms – which are part of a drag link-type steering system – and tie rod ends.

What to do if you hear a clunking noise

If you hear an odd noise, you should make a note of what it sounds like – whether it’s a clunking, squeaking, groaning, moaning or popping. 

We also recommend that you pay attention to when you hear it, or what you are doing at the time. Are you turning, speeding up, slowing down, or going over a speed bump?

These details can be shared with a mechanic or a car repair shop near you, saving them a lot of time by helping narrow down what’s causing the sound.

Being honest when talking to an automotive professional is also helpful. If you have been in a car accident or hit a curb recently, we suggest you mention it. That may be the clue needed to determine the problem.

Tracking down a sound through diagnostic testing, as well as ordering and installing any necessary parts does take time. So, don’t be surprised if the mechanic or auto repair shop asks to keep the vehicle for a few days.

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. 

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Diagnostic testing on a Toyota Tacoma

In Automotive Diagnostics by HomeTowne Auto Repair & Tire

Diagnostic testing is a process of elimination.

As our technicians work on vehicles, they determine where the problem lies and, through research and communication with the customer, figure out the cause.

Some issues, however, aren’t so cut and dry.

A Toyota Tacoma was brought in because it would occasionally stutter when going uphill, even after the driver let off of the accelerator. The symptom started recently and was growing worse.

What we did to figure out the problem

First, we took the truck on a couple of test drives and checked for Technical Service Bulletins (TSBs). 

Then, one of the techs performed a transmission drain and fill to get rid of any contaminants. While the problem did get better, it didn’t go away completely.

This led us to take a look over parts and determine that it may need a new transmission.

The complexity of diagnostic testing

There’s not always one way to approach everything. Sometimes, cars have mechanical failures that don’t trigger a trouble code, which acts as a starting point. 

In the case of the Toyota, the symptom being described felt like many problems – a shift shutter, a misfire, a bad tire – and was intermittent. 

Rather than following a diagnostic tree that a manufacturer provides, we need to use logic and experience to isolate the issue. 

This includes checking fluid levels and, sometimes causing a fault to ensure that components are working. For example, we may purposefully leave a sensor unplugged to see if it will cause a circuit code.

With the Tacoma, it was a mixture of possible misfires, differential problems and transmission problems.

This is why we can’t say that one level of diagnostic testing is needed to address an issue. It could require further investigation. We just don’t know until we start working on it. 

Read about why diagnostic testing is important.

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.

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Did your check engine light turn on? Here’s what you need to know.

In Automotive Diagnostics by HomeTowne Auto Repair & Tire

The check engine light turning is one problem that can be worrisome for drivers. 

When this indicator refuses to go off when someone is starting their car, or when it appears as they’re heading down the highway, it tends to come with the “Uh-oh,” reaction.

So, what should you do when a check engine light turns on?

If the symbol is flashing, you need to have it looked at right away. 

A flashing check engine light means that there’s a problem with the engine. Choosing to wait it out could damage the catalytic converter.

If the indicator is solid, it doesn’t need immediate attention. However, it’s important to have a mechanic check it out as soon as possible.

Can you drive with a check engine light on?

You shouldn’t drive if the light is flashing.

It’s OK to keep driving if it is solid, but it’s a good idea to have it checked out that same day. 

We recommend this because if it’s dangerous you’ll want to have it fixed immediately. Secondly, if you put it off too long you can get several more codes that could be related to the first one. You will likely spend more money on diagnostic testing so the auto repair shop can sort it all out.

What can cause a check engine light to come on?

There are many reasons why the light turns on, some are simple while others are more complex.

It could be anything from low oil to issues with a component, such as the catalytic converter or the coolant system.

Others causes include problems with the ignition system, fuel injection system, evaporative system – which has to do with your gas tank and gas cap – and sensors that are on various parts of the engine.

Check engine light causes graphic.

What do we do during check engine light diagnostic testing?

Diagnostic testing starts with performing a basic check, which helps us rule out any simple problems.

Our technicians then do a preliminary code scan, which gives us a starting point, and start testing related parts.

We follow the testing procedures the manufacturers recommend and look for any Technical Service Bulletins (TSBs) and updates.

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.