Engine Diagnostic Service in San Rafael, CA
When your check engine light comes on, don't ignore it. At AmayaS' Auto Repair in San Rafael, we use advanced OBD-II diagnostic equipment to quickly identify the root cause of engine problems, from emissions issues to AC system faults.
Our experienced technicians analyze diagnostic trouble codes, perform visual inspections, and provide a clear, honest assessment of what your vehicle needs. No guesswork, no unnecessary repairs.
Our engine diagnostics cover:
- Check engine light diagnosis
- OBD-II trouble code scanning and analysis
- Engine performance testing
- Emissions system diagnostics
- Sensor and electrical system testing
- Fuel system diagnostics
- Ignition system analysis, issues here can also affect your transmission
- Pre-purchase vehicle inspections
Once we identify the issue, we'll explain your options clearly and provide a written estimate before any work begins. You decide what gets done, no pressure.
Looking for full-service auto repair? Visit our Hoag Street location.
Check Engine Light On?
Don't panic, but don't ignore it. A check engine light can mean anything from a loose gas cap to a serious engine issue. The only way to know is a diagnostic scan.
- Fast, accurate code reading
- Plain-English explanation
- Written estimate before any repairs
- No charge for scan with approved repair
No appointment needed, walk-ins welcome.
Common Reasons Your Check Engine Light Is On
Oxygen Sensor Failure
Affects fuel efficiency and emissions. One of the most common triggers.
Loose or Damaged Gas Cap
A simple fix that triggers the light. We'll check this first.
Catalytic Converter Issues
Can cause reduced performance and failed emissions tests.
Mass Airflow Sensor
Affects fuel mixture and can cause rough idling or stalling.
Spark Plugs or Ignition Coils
Worn plugs cause misfires, rough running, and poor fuel economy.
EVAP System Leak
A leak in the emissions system that needs to be sealed.
These are just the most common causes, there are hundreds of possible trouble codes. Don't guess. Get a proper diagnostic scan at AmayaS'. Call (415) 747-8541.
How Our Diagnostics Work
Scan
We connect to your vehicle's OBD-II port and read all stored trouble codes.
Analyze
Our technicians interpret the codes and perform hands-on inspections to confirm the root cause.
Explain
We walk you through what we found in plain English, no tech jargon, no pressure.
Estimate
You receive a written estimate. You decide if and when to proceed with repairs.
When to Get a Diagnostic Scan
Your check engine light, service engine soon, or MIL light is on
Your vehicle is running rough, idling unevenly, or stalling
You notice reduced fuel efficiency or power loss
Your car failed a smog or emissions test
You hear unusual knocking, pinging, or ticking from the engine
You're buying a used car and want a pre-purchase inspection
A warning light came on and went off, the codes are still stored
Even if the light turns off, diagnostic trouble codes stay stored in your vehicle's computer. It's always worth getting checked.
Engine Diagnostics FAQs
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Serving All of Marin County
Check-engine lights don't pick favorites, we diagnose vehicles from across the county, including Novato commuters, San Anselmo families, and Fairfax residents. See our full service area.