Why Is My Check Engine Light On?

Modern vehicles are incredibly complex, controlled by dozens of computer modules. When a sensor detects data outside of normal parameters, it triggers the Check Engine Light (CEL). At Ladson Auto Repair Shop, our ASE-certified mechanics don't just "guess" based on a code—we physically test the failing components to ensure a permanent fix.

Free Parts Store Scan vs. Professional Diagnostics

A Parts Store Scan: Only tells you what system is complaining (e.g., "O2 Sensor Code"). It doesn't tell you if the sensor is broken, or if there is a hole in the exhaust causing the sensor to read incorrectly. They want to sell you parts.
Our Professional Diagnostics: We use bidirectional OBD-II scanners, multimeters, and smoke machines to find the root cause of the problem, saving you from buying unnecessary parts.

Common Check Engine Codes We Fix

If you've had your car scanned and received one of these codes, bring it to our shop on Ladson Road for an accurate repair:

Common Code	System Issue	Urgency
P0300 - P0306	Engine Misfire (Bad Spark Plugs, Ignition Coils, or Injectors)	High (Do not drive long distances)
P0420	Catalytic Converter Efficiency Below Threshold	Medium (Will fail emissions test)
P0171 / P0174	System Too Lean (Vacuum Leak or Bad Mass Airflow Sensor)	Medium (Poor gas mileage & stalling)
P0442 / P0456	Small EVAP System Leak (Loose Gas Cap, Bad Purge Valve)	Low (Safe to drive to the shop)

Diagnostic FAQs

Is it safe to drive with the Check Engine Light on?

It depends on how the light is behaving. If the light is flashing or blinking, pull over safely and turn off the engine immediately—you are actively damaging the catalytic converter. If the light is solid and the car feels normal, it is safe to drive to our Ladson auto shop for an inspection.

How much does a check engine diagnostic cost?

We charge a standard diagnostic fee for our technician's time and the use of our professional computer equipment. However, in many cases, if you choose to perform the recommended repairs with us, we apply a portion of that fee toward your repair bill.

Do you diagnose ABS and Airbag lights?

Yes. We have the technology to read and diagnose all dashboard warning lights, including ABS (Anti-lock Brakes), SRS (Airbags), TPMS (Tire Pressure), and Transmission warning lights.

Computer Diagnostics