Car repair: what to know

What the job involves, what changes the price, and what to ask a pro.

What car repair is

A repair shop finds the mechanical or electrical fault behind a problem you notice, such as a warning light, a noise, a leak or rough running. You need it when the car is no longer reliable or safe to drive and you want the cause found before parts are replaced.

Signs you need it

  • A warning light stays on or flashes on the dashboard
  • The engine runs rough, stalls or hesitates when you accelerate
  • You hear new knocking, grinding or whining from the engine or drivetrain
  • Fluid is leaking under the car or the temperature gauge climbs higher than usual
  • The car pulls to one side or shakes at certain speeds

What the pro does

  • Reads stored trouble codes and reviews what you saw and when it happened
  • Tests the suspect system, such as ignition, fuel delivery, cooling or wiring, to confirm the cause
  • Writes up the diagnosis and the repair options with parts and labor for each
  • Waits for your approval, then repairs or replaces the failed part
  • Test drives the car, checks the repair, clears codes and explains what was done

What changes the price

Every job is different, so we do not publish prices. These are the things that move the quote up or down.

  • Whether the fault is a simple part or needs deeper testing to find
  • The make, model and age of the vehicle and how hard the part is to reach
  • Whether the part is original equipment, aftermarket or used
  • How much labor the repair takes on that vehicle
  • Whether related parts should be replaced at the same time
  • Whether the diagnosis is charged separately and whether it is credited to the repair

What a written quote should spell out

  • The diagnosis in plain words, with the test results behind it
  • Each part with its name, brand or grade, and whether it is new or remanufactured
  • Labor for each repair step
  • Fluids, gaskets or supplies used during the work
  • Warranty length and what it covers for parts and labor

Questions to ask before you hire

  • What test did you run to find the cause, and can you show me the readings?
  • Is the repair urgent, or can it safely wait?
  • Will you call me before doing any work beyond the approved repair?
  • Are the parts new, remanufactured or used, and what is the warranty on each?
  • Can I have the replaced parts back so I can see what failed?
  • Could this failure have caused any related damage you will check for?

Red flags

  • Lists many unrelated repairs at drop off with no test results
  • Says the car is unsafe but cannot explain the risk
  • Will not put the estimate in writing before work begins
  • Pushes you to approve work over the phone without a written breakdown

What you can do yourself

You can note the warning lights, the speed and temperature when a problem happens, and any recent repairs. You can check the oil and coolant levels when the engine is cool and the car is on level ground. Hire a shop for any work on brakes, airbags, the fuel system or high-voltage wiring.

Licenses and permits

A license is usually not required for general repair work, but auto repair rules differ by state and city. Check with your state or local licensing agency and ask the shop to show any registration it holds.

Car repair questions

How do I know the diagnosis is right?

Ask the shop to show the test results and readings behind the diagnosis. A good shop will explain the cause in plain words and show you the failed part if you ask.

Do I have to approve every recommended repair?

No. Approve the repair that fixes the problem you came in for first, then decide on other items after you have a written list.

Can I get my old parts back?

Ask at drop off, before the work starts. Many shops will return replaced parts if you request it.

About this guide

This national guide is written and checked by infinibell. Rules and conditions differ by place, so local pros are credited on guides for the cities they serve, not on national ones.

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