Check Engine Light Diagnostics

Understanding Your Vehicle’s Check Engine Light

How the System Works

Modern vehicles are equipped with an Electronic Control Module (ECM) that regulates various aspects of the engine. Its primary function is to keep the engine operating at peak efficiency while minimizing emissions. Achieving this balance is no small feat, given strict emission regulations and varying conditions like speed, temperature, and road quality.

Check diagnostic light

Sensors and Inputs

The ECM relies on a variety of sensors to gauge conditions like engine temperature, vehicle speed, and load. These sensors provide the data that the ECM uses to make adjustments. These adjustments can involve altering fuel levels, modifying ignition timing, or changing idle speed.

Oxygen Sensors

Two types of oxygen sensors work in tandem to manage emissions. The primary (upstream) sensor is located in the exhaust before the catalytic converter. This sensor measures the quality of combustion in the cylinders and sends data back to the ECM. The ECM uses this information to fine-tune the air-fuel mixture, further reducing emissions. A secondary (downstream) sensor, located after the catalytic converter, monitors the converter’s efficiency.

Additional Systems

Other systems, such as the Evaporative system (EVAP), help prevent gasoline vapors from escaping into the atmosphere. The ECM also controls these additional systems and their associated sensors and actuators.

Self-Diagnostic Capability

One of the ECM’s key features is its self-diagnostic ability. It continuously tests the operation of various sensors and components. When it detects an abnormality or missing signal, it triggers the “Check Engine” or “Service Engine Soon” light—also known as the Malfunction Indication Light (MIL). This action is accompanied by the storage of a Diagnostic Trouble Code (DTC) in the ECM’s memory.

Interpreting Trouble Codes

These stored codes can be read using a special scan tool. Although the code provides a general direction for troubleshooting, it doesn’t pinpoint the exact issue. Technicians need to perform specific tests based on each code to determine the true cause of the problem.

Common Triggers

Even seemingly minor issues, like a loose gas cap, can activate the “Check Engine” light. Mechanical failures in controlled systems, such as a faulty EGR valve, will also trigger the light.


Check Engine Light Diagnostics at P.B. Foreign and Domestic Car Repair

When to Seek Check Engine Light Diagnostics

Is your check engine light on? Don’t ignore it! This light is your car’s way of telling you something needs attention. Whether it’s a minor issue or something more severe, our expert Car Care technicians can diagnose the problem.

What Our Check Engine Light Diagnostics Include

Our comprehensive diagnostics service aims to identify the root cause of that annoying check engine light. Our services include:

  • Code Reading: Using state-of-the-art equipment to read error codes.
  • Initial Assessment: Understanding the immediate issues that may be affecting performance.
  • Further Investigation: Additional tests to rule out false readings or underlying issues.
  • Consultation: Discussing the findings with you to decide the best course of action.
  • Repair and Reset: Once the issue is identified and fixed, we’ll reset the check engine light.

Why Choose Us for Your Check Engine Light Concerns?

Don’t leave your car’s health to chance. A lit check engine light can signify a variety of issues, some of which can be severe. Trust the expertise of P.B. Foreign and Domestic Car Repair to correctly diagnose and treat your vehicle’s ailments.

Contact Us

If your check engine light is on and you need professional diagnostics, schedule an appointment or give us a call at 1-858-270-1142.

Need auto repair or car maintenance? Are you in Pacific Beach? Schedule an appointment for a free inspection.

Auto Repair Services

Types of Vehicles We Repair

Servicing a wide range of vehicle types.

Models of Vehicles We Repair

Expertise in various vehicle models.

Jack Kreile
Jack Kreile
August 8, 2023

I’ve been bringing various cars to PB Foreign & Domestic for over 30 yrs. Once agsin, on Monday they provided the best car & customer service I have come to expect from this shop.

I highly recommend them for all your car service needs.

’85 Honda Accord
’97 Nissan Altima
’03 350z
’03 Lexus ES 300
’15 Hyundai Genesis

Diane Greene
Diane Greene
July 29, 2023

Dan, the mechanic is very skilled and honest. I highly recommend asking for him.

ira farnham
ira farnham
June 6, 2023

Great family owned business, run a cool father and son duo. I’ve been taking my cars here for over a decade.

I’ve come across 2 types of mechanics over the years: 1) fixes what needs fixing, checks everthing else out, tells the customer what to keep an eye on/expect in the future. 2) fixes what needs fixing and EVERYTHING else that it touches.

PB Foreign and Domestic is type 1) – straightforward, steady, and honest – which is why I keep coming back and I suspect it’s why the same guys have been working there for forever too.

Aran Osborne
Aran Osborne
April 9, 2023

Best service, best price, they do a great job and are honest! Family owned and operated. I will continue to take my car here. For regular oil changes and maintanance, George is awesome and everyone he employs, this place is great no complaints! Always will look at something if you have a concern like I did. Minor and didn’t Rip me off like most places would have.

Linda Gould
Linda Gould
February 19, 2023

I truly feel like I’m getting the service that’s required and not being upsold on things I don’t need. The price is always better than anywhere else I’ve looked and repairs done timely. They always call if the estimate given to me ends up being different, sometimes it’s lower and if it’s higher they clearly explain why and if it’s absolutely necessary or a recommendation. I trust them.

Jonathan Grannick
Jonathan Grannick
November 18, 2022

If you want a local independent family owned car mechanic that is honest, trustworthy, reasonably priced, and not trying to nickel & dime you these are your guys! Aaron is especially a pleasure to deal with. He went above and beyond at my last oil change to help me on a few things that would have taken tons of time to figure out on my own, you can tell he enjoys helping people (when they aren’t too busy) and is just a personable good natured guy which is so great to have in a car mechanic. Couldn’t recommend them enough!

T. C.
T. C.
May 3, 2022

We really love PB Foreign and Domestic! They have served us well for years on 3 vehicles and have never been disappointed. Highly recommend over dealership or other local facilities. They don’t try to upsell you on things you do not need. Super friendly and can usually get you in within a day or two. It is best to call ahead and make an appointment.

Mandy Anderson
Mandy Anderson
August 25, 2018

Porsche Cayman – my car was overheating so I had my car towed to PB Foreign and Domestic Car Repair. The team was able to repair my car ( I needed a new radiator and water pump) and they gave me very fair pricing. I will definitely come back for my preventitive maintenance.

Need auto repair or car maintenance? Are you in Pacific Beach? Schedule an appointment for a free inspection.