Check engine light diagnostic near me - Seaside & Monterey

March 17, 2025

It’s never a good feeling when your check engine light suddenly turns on. Is it a small issue, or is your engine about to fail? If you're driving in Monterey, Seaside, Pacific Grove, or Carmel, CA, and see that dreaded dashboard warning, don’t panic—Wayside Garage in Seaside, CA, is here to help!

Your check engine light could be triggered by something minor like a loose gas cap or a serious problem like an engine misfire. Let’s break down the most common causes, what they mean, and when you should seek professional help.


What Does the Check Engine Light Mean?

Your check engine light (CEL) is part of your car’s onboard diagnostic system (OBD-II). When your vehicle detects an issue, it triggers the light and stores a trouble code, which a mechanic can scan to diagnose the problem.


There are two types of check engine lights:


🟡 
Solid Check Engine Light – A warning that something needs attention soon.
🔴 
Flashing Check Engine Light – A serious issue that requires immediate service!

💡 Tip: If your check engine light is flashing, pull over safely and call for help—this could indicate an engine misfire that can cause severe damage.


Top 5 Reasons Your Check Engine Light Is On

1. Loose or Faulty Gas Cap

Believe it or not, a loose or cracked gas cap can trigger your check engine light. The fuel system needs to stay sealed to maintain proper pressure.


How to Fix It:

✅ Tighten the gas cap and drive for a few miles—if the light turns off, you’re good to go!
🚗 If the light stays on, you may need a 
new gas cap or further diagnostics.


2. Failing Oxygen Sensor (O2 Sensor)

Your O2 sensor monitors how much oxygen is in the exhaust and helps adjust fuel efficiency. If it fails, your car burns more gas and increases emissions.


Signs of a Bad O2 Sensor:

🔴 Decreased gas mileage
🔴 Rotten egg or sulfur smell from the exhaust
🔴 Rough idling


💡 Fix: Ignoring this can damage your catalytic converter, leading to expensive repairs. Visit Wayside Garage in Seaside, CA, for an O2 sensor check.


3. Bad Spark Plugs or Ignition Coils

Faulty spark plugs or ignition coils can cause misfires, making your check engine light flash.


Symptoms of Bad Spark Plugs:

⚠ Hard starting or rough idle
⚠ Poor acceleration or sluggish engine performance
⚠ Check engine light flashing while driving


💡 Fix: Spark plugs should be replaced every 30,000-100,000 miles, depending on your vehicle. We can check and replace them for you at Wayside Garage!


4. Catalytic Converter Failure

Your catalytic converter helps reduce emissions. If it fails, your car won’t pass a California smog test and may struggle to run.


Symptoms of Catalytic Converter Issues:

⚠ Check engine light stays on
⚠ Reduced fuel efficiency
⚠ Rotten egg smell from the exhaust


💡 Fix: If left unchecked, this can cause costly damageGet a diagnostic check at Wayside Garage before it gets worse!


5. Mass Airflow Sensor (MAF) Failure

Your MAF sensor controls the air-fuel mixture in your engine. If it fails, your engine may stall or hesitate when accelerating.


Signs of a Bad MAF Sensor:

🔴 Rough idling or stalling
🔴 Trouble starting the car
🔴 Decreased fuel economy


💡 Fix: Replacing a faulty MAF sensor early can prevent further engine issues. Stop by Wayside Garage for an inspection!


What Should You Do If Your Check Engine Light Comes On?

🚗 Step 1: Check Your Gas Cap – If it’s loose, tighten it and drive for a few miles.
🛠 
Step 2: Look for Other Symptoms – Is your engine running rough? Is the light flashing?
🔧 
Step 3: Get a Professional Diagnostic Check – Ignoring the problem could lead to expensive repairs!


At Wayside Garage in Seaside, CA, we offer fast and accurate check engine light diagnostics!

📅 Schedule a diagnostic service today! Call us or book online.

👉 schedule your check engine light service!


Why Choose Wayside Garage in Seaside, CA?

✅ ASE-Certified Technicians – Experts in check engine light diagnostics
✅ 
Serving Monterey, Seaside, Pacific Grove & Carmel – Your trusted local repair shop
✅ 
State-of-the-Art Diagnostic Tools – Get the right answer the first time
✅ 
Transparent, Honest Service – No unnecessary repairs—just what your car needs!



📍 Visit us in Seaside, CA, for expert auto repair!


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