8 DIY Car Repairs Most People Should Never Do at Home

  • June 15, 2022
image of DIY mechanic servicing a car image of DIY mechanic servicing a car

It can be tempting to do your own car repairs at home to save money, especially when there are hundreds of places online teaching you how to repair your own car. But oftentimes, the risks can far outweigh the money saved. And at-home car care done incorrectly can result in even more costly repairs down the road! 

While there are a few routine maintenance services you can perform on your own, here are eight DIY car maintenance and repair services you’ll definitely want to avoid.

1. Repair or recharge your AC

Air conditioning is one of the greatest conveniences modern vehicles have to offer. So, when your AC is acting up, you will surely notice. And while it might be tempting to purchase an over-the-counter AC recharge kit as a quick fix, you might want to think twice. 

First, refrigerants are toxic. Though their toxicity levels are generally low, misuse or improper handling of AC refrigerants can be dangerous to your health and to the environment. Second, your vehicle’s AC system is closed, meaning you shouldn’t have to refill or top off your refrigerant. If your vehicle is low on refrigerant, there is likely a leak or a more serious issue, and adding additional refrigerant could be a waste.

Signs it’s time to have your AC inspected

Is it time to schedule an AC service at your local Firestone Complete Auto Care? Look for these symptoms:

  • Car is only blowing hot air
  • AC makes strange noises when it’s on
  • AC only blows cold when driving

2. Mount or balance your tires

Mounting or balancing tires might seem like easy DIY car maintenance, but it’s best left to the professionals. Improper mounting can lead to flat tires, making driving dangerous for you and other drivers on the road. Likewise, improperly balancing your tires at home can cause excessive shaking that can damage other parts of your vehicle. 

Whether you need to swap out your winter tires for summer or all-season tires or just need new tires altogether, you can get professional tire mounting and balancing services from the experts at Firestone Complete Auto Care.

3. Repair the transmission

Your transmission is a complicated system of gears, possibly making transmission repair the hardest car repair to try at home. The average automatic transmission has roughly 800 parts, including gears, pumps, clutches, a torque converter, etc. If you notice any signs that your transmission is in trouble, it’s best to head to your local Firestone Complete Auto Care right away.

Signs it’s time to get your transmission repaired

When functioning correctly, your transmission is responsible for helping your vehicle move. But when you have transmission problems, you can experience various issues, including:

  • Grinding noises or shaking
  • Your car revs higher in between automatic gear shifts
  • Poor driving performance
  • Illuminated malfunction indicator light
  • Burning smell
  • Vehicle will not move when placed in gear

4. Repair your fuel system

There are several components in your fuel system, including the gas tank, fuel filter, fuel pump, fuel lines, and injectors. Attempting to repair or replace any of these components on your own can affect the whole system and cause safety issues or damage other parts of your vehicle. Repairing any component in your fuel system is best left to the professionals at Firestone Complete Auto Care.

Signs it’s time to have your fuel system checked

Fuel system issues can show up in several ways, including:

  • Weird noise coming from your gas tank
  • The engine sputters
  • The vehicle has power surges
  • Decreased fuel efficiency
  • Difficulty starting your car

5. Replace suspension system components

The suspension system holds your vehicle up and helps protect it from unexpected dips and bumps in the road. When one or more suspension parts are damaged or malfunctioning, you may notice that your vehicle is more bouncy when riding over bumps. The vehicle's handling might also feel off, or you could hear odd popping noises while turning. 

Some of these parts can be easy to spot underneath your vehicle and may appear to be easily accessible. But replacing suspension parts can be tricky — and doing it incorrectly can likely lead to many more issues later. 

Certain parts in your suspension system, such as the coil springs, are under immense pressure. Mishandling them can cause serious injury or death, as well as damage other parts of your vehicle. On top of that, replacing a component incorrectly can impact the handling of your ride and may cause premature wear on other car parts. For these and many other reasons, it’s best to leave suspension repair to the pros at Firestone Complete Auto Care.

Signs it’s time to have your suspension system repaired

Is your suspension system not what it used to be? Look for these signs:

  • Excessive bouncing over bumps and dips in the road
  • Your car lunges forward when you brake
  • Oil coming out of the shocks or struts
  • The car sits lower on one or both sides when parked

6. Replace brake pads, rotors, or brake fluid

Brake pad replacement is a necessary routine maintenance service for every vehicle. And while it can be tempting to do it at home to save money on maintenance, replacing your brake pads, rotors, or brake fluid is not the best at-home car maintenance to perform. 

Replacing brake components incorrectly can be a major safety hazard, which can be dangerous for you and other drivers around you. Additionally, electronic parking brakes add an extra layer of complexity if equipped. 

A brake service appointment at Firestone Complete Auto Care is quick and easy, and our experts ensure your brakes are replaced or repaired right the first time. So, next time you're due for brake service, it’s best to leave it to the experts.

Signs it’s time to schedule a brake service appointment

Are your brakes on their way out? You probably won’t be able to ignore one or more of these symptoms:

  • Squealing or grinding sound when you brake
  • It takes a longer distance to come to a complete stop
  • Your car shakes when you brake
  • Soft or spongy brake pedal
  • The BRAKE, ABS, or brake pad wear light is illuminated 

7. Replace timing belt or chain

There may have been a day when changing out an engine timing belt was as simple as doing a puzzle. But today, most modern cars are far too complicated for a simple DIY engine timing belt or chain replacement. 

Replacing an engine timing belt or chain incorrectly can have dire consequences. If the timing belt or chain is even one tooth off, it may cause catastrophic engine failure on an interference engine due to pistons colliding with valves. An improperly installed timing belt or chain could leave just as many if not more parts of your vehicle damaged or inoperable, including your engine! 

Signs it’s time to replace your timing belt or chain

Is it time to schedule a visit to Firestone Complete Auto Care to replace your timing belt or chain? Look for these symptoms:

  • Rattling noises from your engine
  • Multiple engine misfires
  • Malfunction indicator light is illuminated — with related timing codes
  • Your vehicle isn’t starting
  • On board warning saying to replace your timing belt

8. Engine diagnostics or repair

Thinking of doing some DIY car service on your engine? You might want to think again. Your combustion engine is a complex system designed to operate very specifically. One incorrectly installed component may impact how other systems operate and potentially cause damage. Whether it’s pistons, gaskets, sensors, or any other engine component, it’s always best to leave engine diagnostics and repairs to a professional.

Signs it’s time for a diagnostic

It’s time for a diagnostic if you notice any of these symptoms:

  • Check engine light is on
  • Engine misfires
  • Your car doesn’t start
  • Loss of power
  • Engine runs or idles rough
  • Knocking sound in engine
  • Overheating

Trust the Experts for All Your Car Repairs

When it comes to your vehicle, it’s important to know which repairs you can do at home and which ones to avoid. For the ones you can’t, Firestone Complete Auto Care is here to help. Our team of professional technicians understand the ins and outs of your vehicle and can help get it back on the road. Whether it’s brake repair, an engine diagnostic, or a complete vehicle inspection, Firestone Complete Auto Care can give your car the expert repairs it deserves. Call your local store or make an appointment online.

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