Why is my check engine light on?

June 10, 2024


Check Engine Light: A Deep Dive at Wayside Garage

At Wayside Garage in Seaside, CA, we recently had a client come in with a Chevy Volt experiencing a check engine light issue. The modern Chevy Volt, like many vehicles today, is equipped with approximately 30 to 50 different computers, each monitoring various systems and components. 


When diagnosing a check engine light, our first step is phase one testing, where we scan the vehicle's computer for codes. In this particular case, our expert technician, Jonathan, found multiple codes stored in the computer. Some of these codes were even duplicated across different modules.


Decoding the Codes: A Layman's Explanation

To make sense of this, think of the car as the trunk of an oak tree. When we plug the scanner into the vehicle, it's like identifying the trunk. Each code we find directs us to a specific branch, and from there, we may need to examine smaller branches and leaves to find the exact issue. 


Many people think that diagnosing car issues is as simple as plugging in a machine that spits out a magical repair solution. In reality, it's much more complex. Jonathan often works on hybrid and electric vehicles, running tests with tools like fluke meters and lab scopes. It's a bit like playing detective for cars!


The EGR Issue: A Common Problem

In this case, the client was particularly concerned about an EGR (Exhaust Gas Recirculation) issue, a common failure point in many vehicles. Upon inspection, Jonathan found that the problem wasn't the EGR valve itself but rather an electronic issue with the computer. 


Interestingly, this particular issue has led to a recall because it's been reported in thousands of similar vehicles. Unfortunately, due to high demand, the replacement part is on backorder. This means that some of the check engine light codes may persist until the defective component is replaced.


The Interconnected Nature of Modern Vehicles

Modern vehicles are incredibly interconnected. Computers in your car communicate with each other using binary codes. When one system has a problem, it can affect others, sometimes leading to what we call "false codes." This makes diagnosing issues a bit like untangling a web, as problems in one area can cause multiple modules to shut down or throw flags.


Trust Wayside Garage for Accurate Diagnostics

If you have a check engine light issue, it's important to address it promptly to prevent further damage to your vehicle. At Wayside Garage, we use top-of-the-line diagnostic equipment and have a team of certified technicians ready to help. 


Give us a call at (831)-899-2425 or visit our website at www.waysidegarage.com to schedule your reservation. We'll ensure your vehicle is running smoothly and safely.



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How Do I Know If My Tires Are Safe to Drive On? Tips from Wayside Garage in Seaside, CA for National Tire Safety Week Tire safety is one of those things drivers don’t think about — until it’s too late. But as a local shop owner with over 38 years under the hood, I can tell you: the health of your tires has a major impact on how your car handles, brakes, and keeps you safe out on the road. That’s why we’re proud to support National Tire Safety Week 2025 , happening June 30 to July 4 — an annual effort from the U.S. Tire Manufacturers Association to educate drivers on proper tire maintenance. And right here at Wayside Garage in Seaside, CA , we’re doing our part to help folks check in before they check out for summer road trips. πŸš— So, How Do You Know If Your Tires Are Safe? It really comes down to four key checks — easy to remember with the acronym P.A.R.T .: πŸ”Ή P = Pressure Low tire pressure leads to poor fuel economy, sluggish handling, and faster wear. We recommend checking pressure monthly, especially before long drives. Always check when your tires are “cold” — that means before you hit the road, not after a grocery run. πŸ”Ή A = Alignment If your car’s drifting left or right, or your steering feels off, your alignment may be out of whack. Misalignment causes uneven wear, hurts handling, and can shorten your tire life — not to mention your patience. πŸ”Ή R = Rotation You’d be surprised how fast tires can wear unevenly. We rotate tires every 5,000–7,500 miles to make sure all four tires wear evenly. This extends tire life and keeps your vehicle handling the way it should. πŸ”Ή T = Tread Tires need grip, especially in wet or winding road conditions. We recommend checking tread depth monthly. If your tire tread is worn down to 2/32 of an inch or less — or if you see visible cracking or bulges — it’s time to replace them. πŸ’‘ Quick Tip: Stick a penny into your tread, Lincoln's head down. If you can see all of Honest Abe's noggin, your tread is too low. πŸ› οΈ What We Offer at Wayside Garage, Seaside CA We’ve been serving the Seaside community for nearly four decades, and tire safety is something we don’t take lightly. Our tire services include: Tire pressure checks and adjustments Computerized wheel alignments Tire rotations and balancing Tread inspections and honest tire replacement recommendations Tire age checks — rubber breaks down over time, even if your tread looks good. Most tires should be replaced every 6 years, regardless of wear. Whether you're planning a road trip or just commuting to work, swing by Wayside Garage in Seaside for a tire check. No pressure (pun intended) — just experienced, straightforward service you can trust. ❓ FAQ: Tire Safety Questions We Hear All the Time Q: How do I know when my tires need to be replaced? A: If your tread is worn past 2/32", your tires are over six years old, or you notice bulges or cracks — it’s time to replace them. Q: How often should I rotate my tires? A: Every 5,000 to 7,500 miles. We include this as part of routine maintenance at Wayside Garage. Q: Can alignment affect tire wear that quickly? A: Absolutely. One pothole or curb can knock alignment off. If your car pulls or your tires wear unevenly, it’s time for an alignment check. Q: What tire pressure should I use? A: Check your driver’s door sticker or owner’s manual — never use the number printed on the tire itself. 🏁 Drive Into Summer with Confidence This National Tire Safety Week , don’t just guess your tires are safe — know they are. Bring your vehicle to Wayside Garage in Seaside, California and let our experienced team give your tires a full safety check. You’ll leave knowing your pressure’s perfect, your alignment’s dialed in, and your tread is road-trip ready. Stop by or schedule your service today — we’re here to keep you rolling, safely.
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