Check Engine Light Experts

Professional diagnosis and fix for check engine lights and other warning indicators.

Check Engine Light Diagnosis

That illuminated check engine light can signal anything from a loose gas cap to a serious engine problem. Our first step is a qualified diagnosis using advanced scan tools to read the stored trouble codes. However, codes alone only point to a problem area; they don't always identify the failed component. Our specialists are technicians at interpreting this data and performing further tests to find the root cause. We provide a clear explanation and transparent options for repair, so you know exactly what's wrong and what it will take to fix it.

Common Causes in Marin County

In our Novato climate, we often see issues related to heat and humidity. Evaporative emission system failures, often triggered by a faulty gas cap or vent valve, are common. Oxygen sensors can be affected by coastal air, and high underhood temperatures can stress ignition components. We have extensive experience with these region-specific failures and know the most dependable fixes. Don't ignore the light; let us quickly diagnose the issue and get you back to confident driving.

What to Do When the Light Comes On

If your check engine light is steady, it's advisable to schedule an appointment soon. If it's flashing, you should reduce driving load and seek maintenance immediately, as this indicates a severe misfire that can damage the catalytic converter. Avoid simply disconnecting the battery to reset the light, as this erases valuable diagnostic data. Bring your vehicle to Leonardi Automotive, and we'll use that data to quickly pinpoint the problem. We make understanding and fixing your check engine light simple.

Services We Offer