Check Engine Light On? Do This First (Before You Pay for Anything)

0:00 The check engine light just came on.

0:01 Your stomach drops and you start wondering what this is going to cost.

0:06 Take a breath.

0:07 In the next few minutes, I'll show you what to do first, when it's safe to keep driving, and when you need to pull over right now.

0:15 The first thing to check is how the light looks.

0:18 A solid light usually points to an emissions problem, or another fault the car has flagged.

0:23 You can generally keep driving, but get it looked at as soon as you can.

0:27 A flashing light is different.

0:29 It signals a severe problem that can damage critical parts of the car.

0:33 Pull over somewhere safe and turn the engine off.

0:36 Don't keep driving it.

0:38 Also, if an oil pressure or temperature warning comes on along with the check engine light, stop in a safe place and shut the engine off.

0:46 Engine damage can happen fast.

0:49 If the light is solid and the car feels normal, check your gas cap.

0:53 A loose cap can trigger the light.

0:55 Tighten it until it clicks.

0:57 If that was the problem, the fix cost you nothing.

1:00 If the cap is damaged, a new one runs about $25.

1:03 The light only tells you something is wrong.

1:06 A code tells you what.

1:08 Many auto parts stores will read the code for free.

1:11 A repair shop usually charges under $100 for a diagnostic scan, and many shops will waive that if you have them do the repair.

1:18 You can also buy your own OBD-II scanner, often for under $50.

1:23 One important point.

1:24 A code is a clue, not a final answer.

1:27 It tells you where to look.

1:29 It doesn't always tell you which part to replace.

1:32 Here are some common causes, with Kelley Blue Book's approximate dealer prices using original-equipment parts.

1:38 Independent shops can differ.

1:40 Loose gas cap, free to tighten.

1:43 Oxygen sensor, about $350.

1:46 Spark plugs or plug wires, about $400.

1:50 Mass airflow sensor, about $500.

1:54 Fuel injectors, about $1,200.

1:57 Catalytic converter, $2,000 or more.

2:00 Your price will depend on your car and your area, so use these as a rough guide, not a quote.

2:06 Before you say yes to a repair, ask:

2:08 What code did you find, and can I see it?

2:11 What did you test to confirm that part is the problem?

2:14 Can you give me the price in writing, with parts and labor separated?

2:17 And if I decline, will I still owe a diagnostic fee?

2:21 So, solid light, check the cap and get the code read.

2:25 Flashing light, pull over safely.

2:28 And never agree to a repair you don't understand.

2:30 If this helped, subscribe to Car Care Decoded.

2:33 Next time, I'll explain how to read an estimate, line by line.

2:37 This video is general information only, so always have your own vehicle inspected by a qualified technician.