Anthony Harlin, ASE Certified Master Automobile Technician

Technical Reviewer at CarParts.com

Tony Harlin is a Master Gas and Diesel Diagnostic Technician with over 18 years of experience. He works full-time at a large independent automotive shop as a driveability and repair technician working on all types of vehicles with a focus on diesels. ASE certifications include A1-A9, L1 and L2, as well as X1.

Tony has a YouTube channel, “Nuts & Bolts with Tone,” with over 25,000 subscribers, devoted to automotive troubleshooting, repairs as well as tool demos and reviews. When not working on cars, Tony enjoys spending time with his three sons and wife in Sacramento, California.

Credentials:

  • ASE A1-A9

  • L1 & L2 Advance Engine Performance Gas & Diesel X1 Exhaust Systems

What Does It Mean When the Engine Is Hot While the AC Is Off?

Summary If you’re wondering what a hot engine means if the AC is off, then there’s a good chance that…

3 years ago

What is Payload vs Towing Capacity? How to Calculate and More

Summary Payload capacity is the amount of weight a vehicle can carry, while towing capacity is the amount of weight…

3 years ago

What Is a Transmitter Pocket? (Plus FAQs)

Summary A transmitter pocket is a compartment for your vehicle’s key fob that lets you start the engine or leave…

3 years ago

What Is a Powertrain Malfunction?

Summary A powertrain malfunction is a general term used to describe a problem in the engine or transmission.The powertrain refers…

3 years ago

What Does Resetting the Transmission Module Do? How and When to Reset

Summary Resetting the transmission control module (TCM) reestablishes its factory settings and makes it forget what it has previously learned.…

3 years ago

What Are the Common Problems of the Instrument Cluster?

Summary Common instrument cluster problems include faulty backlights, inaccurate or no gauge readings, and malfunctioning LCD screens. It can also…

3 years ago

What Can I Plug Into My Car’s 110V Outlet?

Summary Having a 110V outlet in your car is just like having a portable charging station. This means you can…

3 years ago

What Cars Can Be Flat Towed Behind Your RV?

Summary Flat towing is a method where a motorhome or RV pulls another vehicle. A tow bar on the front…

3 years ago

What Is IVT? Intelligent Variable Transmission Explained

Summary IVT stands for “Intelligent Variable Transmission.”IVT is a transmission setting that improves your vehicle’s fuel economy and makes your…

3 years ago

What Happens When a Car Reaches Maximum Mileage?

Summary Two scenarios could happen once you max out the mileage on your vehicle. The odometer could reset to zero…

3 years ago

Understanding Dashboard Warnings: What Does a Triangle With an Exclamation Point Mean?

Summary A triangle with an exclamation point is called a master warning light or general warning light. It indicates there's…

3 years ago

What Does Service Shifter Mean?

Summary The service shifter warning indicates an issue with the gear shifter and the need to service the part.The gear…

3 years ago

What Happens When a Tie Rod Breaks?

Summary The wheels will lose their connection to the steering assembly if the tie rod end breaks.The tire rods allow…

3 years ago

What Does Resetting the PCM Do?

Summary Resetting the PCM puts your car back to its factory settings. Experts usually recommend resetting the PCM to clear…

3 years ago

What Does Service 4WD Mean? Triggers, How to Clear, and More

Summary The service 4WD message or light appears when there’s a possible issue in the 4WD system that may require…

3 years ago

What Does an Emission System Problem Mean?

Summary An illuminated check emission system light means there's a faulty component affecting the vehicle's emission control.Some common issues that…

3 years ago

What Does FCW Mean in a Car?

Summary FCW stands for "forward collision warning," a security feature that alerts drivers when there's an obstacle detected in front…

3 years ago

What Does BSM Mean on a Car?

Summary BSM stands for blind-spot monitoring.BSM systems use cameras and radars to detect nearby vehicles and pedestrians in the driver’s…

3 years ago

What Does a Battery Saver Do?

Summary If the battery is weak or unable to hold a charge, the powertrain control module will trigger a “battery…

3 years ago

What Is DTE In a Car?

Summary DTE stands for “distance to empty.” It’s how far your vehicle can travel before it runs out of fuel.Not…

3 years ago

What Does Check Gauges Mean?

Summary An illuminated check gauge light means that one or several gauge readings aren’t within the normal range.Low oil pressure,…

3 years ago

What Does Active Fuel Management Mean?

Summary An active fuel management (AFM)-equipped engine deactivates cylinders by collapsing the corresponding valve lifters, which effectively stops the intake…

3 years ago

What Is a Sealed Transmission?

Summary Sealed transmissions are sealed off completely with no easy way to get to the fluid inside. Other than this…

3 years ago

What Is a TIPM and What Does It Do?

Summary A Totally Integrated Power Module (TIPM) is a fuse box, relay box, and electronic module all rolled into one.A…

3 years ago

What Does the Transfer Case Control Module Do for Your Vehicle?

Summary The transfer case control module runs the four-wheel drive (4WD) drivetrain and controls the process of shifting gears when…

3 years ago

What Is a PTC Heater?

Summary Positive temperature coefficient (PTC) heaters help the vehicle’s heating, ventilation, and air conditioning (HVAC) system heat air inside the…

3 years ago

What Is a Small Block Engine?

Summary A small block engine has small bores strokes, ports, and valves. Still, it’s capable of generating up to 5,800…

3 years ago

What Is the Biggest Problem with Hybrid Cars: Is Going Green Worth it?

Summary Hybrid vehicle batteries generally last up to eight years or 100,000 miles. Over time, they won’t be able to…

3 years ago

What Does a Transmission Slip Feel Like?

Summary You can tell your transmission is slipping when it feels like you’re driving over ice or changing gears without…

3 years ago

What Causes a Transmission Not To Shift?

Summary Low or dirty transmission fluid, a malfunctioning PCM, and other electrical issues can prevent the transmission from shifting properly.…

3 years ago

What Is a Big Block Engine and How Is It Different From a Small Block Engine?

Summary Big block engines have big bores, valves, and ports, allowing them to produce tremendous amounts of power.Small block engines…

3 years ago

What Does xDrive Mean on Your BMW?

Summary xDrive is the proprietary all-wheel drive system of BMW, and it’s a feature that’s available in many BMW vehicles.xDrive…

3 years ago

What Does a Battery Discharge Warning Mean? Meaning and Troubleshooting Tips

Summary Using electrical components when the engine Is off discharges the battery.An illuminated battery discharge warning light can be caused…

3 years ago

What Does VSA Mean In a Car?

Summary VSA is a type of electronic stability control that automatically adjusts engine output and applies the brakes when in…

3 years ago

Where Is the Cooling Fan Switch Located?

Summary The cooling fan switch is usually on the radiator assembly. Not all engines come with a fan switch. In…

3 years ago

Where Is the Anti-Theft Fuse Located?

Summary The anti-theft fuse is typically in the fuse box on the driver’s side. Depending on the vehicle’s specifications, the…

3 years ago

What Happens If You Mix 93 and 87 Gas?

Summary Nothing happens when you mix 93 (premium) and 87 (regular) octane gases. The mix is called “midgrade” gas.Some of…

3 years ago

Are Wider Tires Better Than Narrow Tires?

Summary Wide tires offer improved traction and increased brake efficiency. They also give vehicles a more muscular look while improving…

3 years ago

What Is a Rear Differential Seal? Replacement Costs, Procedure, and Other Related FAQs

Summary The rear differential seal is a seal in the differential that prevents the fluid from leaking out.You may need…

3 years ago

Fuel Low: What Does the Low Fuel Light Mean?

Summary The low fuel level warning light turns on when there’s inadequate fuel in the gas tank.  It illuminates when…

3 years ago

EGR Solenoid: Function, Symptoms, and FAQs

Summary The EGR solenoid distributes engine vacuum to the EGR valve.The smell of unburnt fuel, knocking sounds, and a failed…

3 years ago

What Does TCS Mean in a Car?

Summary TCS stands for “traction control system.”The TCS helps your vehicle maintain stability while driving on low-traction surfaces. The TCS relies…

3 years ago

Car Steam Cleaning: What Makes It So Great and Other FAQ

Summary A steam cleaner effectively kills bacteria, getting rid of unwanted smells.You can use a steam cleaner to clean the…

3 years ago

What Are Ventilated Seats and Are They Worth It?

Summary Ventilated seats are made from perforated plastic and have fans and ducts.The fans draw air from under the seat…

3 years ago

What Does the Wrench Light Mean?

Summary An illuminated wrench light on your dashboard usually indicates that your car requires professional service. This tends to differ…

3 years ago

Driving Terrors: The Death Wobble

Summary Death wobble is a rapid oscillation of various steering system components that causes the steering wheel to move from…

3 years ago

What Is EcoBoost On A Car?

Summary Ford’s EcoBoost has three key features, including direct fuel injection, turbocharging, and variable camshaft timing.The EcoBoost engine is an…

3 years ago

What Is a VTEC Engine and How Does It Work?

Summary The Honda Variable Valve Timing and Lift Electronic Control (VTEC) is an engine system designed to give drivers a…

3 years ago

What Is Chassis Control in Nissan Vehicles?

Summary Chassis Control is a suite of three specific systems in modern Nissan vehicles that allow their drivers to have…

3 years ago

What Are Boxer Engines?

Summary Boxer engines are a type of flat engine with a cylinder bank angle of 180 degrees. The term “boxer”…

3 years ago

What Is a 2JZ Engine and Why Is It So Popular?

Summary Manufactured by Toyota, the 2JZ is a powerful engine with an inline-six cylinder unit. It has two inline-three cylinder…

3 years ago

What Is a Car LSD?

Summary A limited-slip differential (LSD) is a type of differential, which is a gear train that allows the wheels on…

3 years ago

What Is an Adaptive Front-Lighting System?

Summary Also known as adaptive headlights, an adaptive front-lighting system (AFS) is able to adjust the direction and angle of…

3 years ago

What’s the Right Torque for Lug Nuts?

Summary Most wheel lug nuts require around 100 pound-feet of torque, but some wheels might require more or less torque.…

3 years ago

What Happens if You Disconnect Your Car’s Throttle Position Sensor?

Summary Disconnecting the throttle position sensor (TPS) will cut the powertrain control module (PCM) off from critical information it needs…

3 years ago

What Does the Service StabiliTrak Message Mean?

Summary An illuminated StabiliTrak service light means that the system will most likely be disabled until the issue is resolved.…

3 years ago

Replacing a Throttle Cable: What It Entails Plus Related FAQs

Summary The steps for replacing a throttle cable can vary significantly depending on your ride’s make and model. The process…

3 years ago

Chirping Noise In a Car: What Does It Mean?

Summary If your car is making a chirping noise, you might be dealing with a worn serpentine belt, a failed…

3 years ago

What Is Differential Gear Oil: Uses, Costs, and Other Related FAQs

Summary Also known as gear lube or gear oil, differential gear oil lubricates the metal components in your differential to…

3 years ago

Common Reasons Why Your Car Is Leaning to One Side

Summary If your car is leaning to one side, your vehicle might have tire issues, a twisted chassis, or a…

3 years ago

Common Reasons Why Your Turn Signal Bulb is Malfunctioning

Summary Faulty bulbs, a dead car battery, and a bad alternator are common causes of a malfunctioning turn signal bulb.Replacing…

3 years ago

A Handy Guide to Steering Box Adjustment

Summary Adjusting the steering gear box is something you need to know if you want to keep your car in…

3 years ago

Why Are Your Dashboard Lights Not Working When the Headlights Are On? Plus Related FAQs

Summary Dashboard lights usually dim when the headlights are on because the vehicle adjusted the dashboard’s brightness based on the…

3 years ago

Failing Clutch Slave Cylinder: Symptoms, Causes, Repair, & FAQs

Summary The clutch slave cylinder disengages the clutch from the engine by moving the pressure plate.When the clutch slave cylinder…

3 years ago

How Do Wheel Locks Work? Tips for Installing and Removing Wheel Locks

Summary Wheel locks are specialty lug nuts that prevent thieves from stealing the wheels and require their wheel lock key…

3 years ago

Getting Your Hands Dirty: Why Your Vehicle Needs Suspension Grease

Summary Suspension components need fresh grease to lubricate their areas and remove contaminants from the joints and the ball-and-bearing assembly.Keeping…

3 years ago

Telltale Signs of a Bad Steering Rack Bushing

Summary Steering rack bushings (a.k.a. rack and pinion bushings) dampen vibrations while making turns. Common symptoms of a bad steering…

3 years ago

Seat Belt Warning Light: What it Means When it’s On

Summary The seat belt warning light is a dashboard light that flashes when it detects that someone isn't wearing their…

3 years ago

What Is a Rotary Engine and How Is It Different From Other Engines?

Summary Rotary engines usually appear in sports cars that need high performance. Rotary engines have a four-step combustion cycle (intake,…

3 years ago

Bad or Failing Main Relay Symptoms

Summary A bad main relay can cause problems like a no-start condition, unreliable vehicle ignition, an engine that won’t stay…

3 years ago

What are the Symptoms of a Bad Timing Gear?

Summary A bad timing gear will create a rattling noise from your engine. Your engine will also run rough or…

3 years ago

Is There a Strong Exhaust Smell Outside Your Car? Here’s Why

Summary You might notice a strong exhaust smell outside your car.The possible reasons for the potent exhaust smell include a…

3 years ago

Why Won’t My A/C Blow Cold Air? Common Causes and Prevention Tips

Summary If your A/C won’t blow cold air, then your A/C system might have low refrigerant levels, a clogged air…

3 years ago

Recognizing the Symptoms of a Bad Window Regulator

Summary Window regulators lift and lower your car’s window panels using a mechanism that consists of brackets, gears, and cables.…

3 years ago

7 Key Differences Between Diesel and Gas Engines

Summary The main difference between diesel and gas engines is in the fuel they use. Gasoline burns faster and produces…

3 years ago

How To Remove Air Pockets in Your Cooling System With a Vacuum Coolant Filler

Summary A vacuum coolant filler is a tool specifically designed to remove all of the air in a vehicle’s cooling…

3 years ago

All About Park Assist: Symbols, Types, and More

Summary Park assist is an automatic parking aid found in many recent vehicle models. Compared to early parking sensors, park…

3 years ago

Why Won’t My Key Fob Open My Car? Possible Reasons Why

Summary If your vehicle won’t lock or unlock with your key fob, it can be a great inconvenience.Possible reasons your…

3 years ago

Can a Car Lose Freon Without a Leak?

Summary When there’s a significant lack of freon in your vehicle’s system, it can cause a number of problems. Refrigerant…

3 years ago

What does API Mean When Talking About Engine Oil?

Summary The American Petroleum Institute (API) sets the bar for oil products. The API seal of certification on engine oil…

3 years ago

Why Does My Car Sound Like a Helicopter?

Summary There are scenarios where vehicles can make a deep, rhythmic thumping sound combined with a high-pitched whirring noise, much…

3 years ago

Hose Clamp Pliers: Your Go-To Tool for Removing Hose Clamps

Summary Hose clamp pliers, also called hose clip pliers, are specifically designed to make pulling out hose clamps easier. They…

3 years ago

Is Warming up the Car Before Driving Necessary? Advantages, Disadvantages, and More

Summary Warming up the engine before departing might feel necessary, but it isn’t always the case. The ideal idle time…

3 years ago

Got a “Transmission Hot Idle Engine” Message On Your Dash? Here’s How to Fix It

Summary The fix for this problem can be as simple as topping up your transmission fluid, repairing or replacing faulty…

3 years ago

How To Use a Tow Bar (Plus Other FAQs)

Summary Tow bars are equipment attached to a vehicle that needs to be towed. The tow bar doesn’t lift the…

3 years ago

Tire Won’t Come Off? Here Are The Reasons It’s Stuck and How to Remove It

Summary A tire might not come off because of rust, warped wheels, or stuck lug nuts. You can use brute…

3 years ago

How to Tell When the Rad Cap Is Leaking: 6 Symptoms

Summary A leaking radiator cap will leak coolant, causing low coolant levels, which can result in overheating.A leaking radiator cap…

3 years ago

Replacing Piston Rings: 5 Signs It’s Time for a Replacement

Summary You might need to replace your engine’s piston rings if your vehicle misfires, emits discolored smoke, has poor acceleration,…

3 years ago

What Are the Different Types of Oil Filters and How Do They Work?

Summary Primary oil filters clean and remove impurities from the oil used in the engine. They’re the most common type…

3 years ago

Why Is My Car Honking When Parked? 7 Causes, Explained

Summary It can be annoying when your vehicle honks on its own. There are a number of explanations behind this…

3 years ago

Battery Drop Test: What It Is, How to Perform It, and Its Significance

Summary Battery drop testing, or voltage drop testing, is a procedure done to find out if the battery cables and…

3 years ago

Why Your Car Struggles to Go Uphill (No Check Engine Light)

Summary Some cars tend to struggle to go uphill due common issues associated with poor power or pull.Reasons your car…

3 years ago

Nissan Altima: “No Key Detected” – 5 Causes and Fixes

Summary “No key detected” is one long-standing and frustrating problem that the Nissan Altima can develop.Reasons your Nissan Altima can’t…

3 years ago

A Definitive Guide to Crossmembers, Frames, and Other Suspension System Principles

Summary A crossmember is a steel or aluminum bar that runs across the vehicle to support the transmission. It’s usually…

3 years ago

What Does the Steering Stabilizer Do? (Plus Other FAQs)

Summary A steering stabilizer, also known as a steering dampener, dampens and absorbs sudden motions in the steering linkage to…

3 years ago

Does Your RPM Jump While Driving? Here Are 10 Reasons Why

Summary The tachometer measures the engine’s revolutions per minute (RPM).The RPM might jump while driving because of bad parts like…

3 years ago

How and When Should You Drain Your Gas Tank?

Summary Before draining your gas tank, make sure to disconnect the negative battery terminals, find a ventilated area, and prepare…

3 years ago

Points and Condenser: Purpose, Symptoms, and FAQs

Summary Most older vehicles have a point-type ignition system, which uses ignition points, a set of electrical contacts that switch…

3 years ago

Why Is My Car So Loud?: 12 Causes of Loud Engine Noise

Summary A bent or clogged tailpipe, a missing or damaged catalytic converter, and an exhaust manifold leak are common reasons…

3 years ago

Symptoms of a Bad Brake Booster Sensor and Other FAQ

Summary Common symptoms of brake booster sensor failure include an illuminated check engine light, a stiff brake pedal, and a…

3 years ago