Welcome to On Site Auto Repair!
Complete Auto Repair Services in Santa Rosa, CA
Expert Automotive Service for All Makes & Models
- ASE-Certified Technicians: High-quality, safe automotive services.
- Latest Diagnostic Technology: Quick turnaround times to get you back on the road.
- Serving Sonoma County: Trusted by Santa Rosa, Petaluma, Sebastopol, and Windsor drivers since 2010.
Serving Santa Rosa Since 2011
★★★★★ 4.9/5 (117 Google Reviews)
Our Auto Repair Services
Brake Services
Your safety depends on reliable brakes, whether you’re navigating Santa Rosa’s hills or Wine Country roads.
Services Include:
- Brake pad and shoe replacement
- Rotor and drum repair/replacement
- Brake fluid service and bleeding
- Caliper and wheel cylinder repair
- ABS system diagnostics
- FREE brake inspections
Engine Services & Repair
From check engine lights to complete rebuilds, our engine specialists keep your vehicle running strong.
Services Include:
- Engine diagnostics and repair
- Tune-ups and maintenance
- Timing belt replacement
- Head gasket repair
- Engine rebuilds and replacement
- Performance upgrades
Perfect for Santa Rosa commuters and Wine Country adventurers
Free engine diagnostics with repair
Transmission Service & Repair
Transmission problems? Our experts diagnose and repair both automatic and manual transmissions.
Services Include:
- Transmission fluid service
- Filter replacement
- Transmission repair and rebuild
- Clutch replacement (manual)
- CV joint and axle repair
- Transfer case service
Free transmission diagnostics | Serving all Santa Rosa neighborhoods
Electrical System Service
Modern vehicles rely on complex electrical systems. Our technicians diagnose and repair electrical issues quickly.
Services Include:
- Battery testing and replacement
- Alternator and starter repair
- Ignition system service
- Wiring harness repair
- Computer diagnostics
- Lighting system repair
Advanced diagnostic equipment for accurate repairs
Steering & Suspension Services
Smooth, safe driving starts with proper suspension, especially on Santa Rosa’s varied terrain.
Services Include:
- Shock and strut replacement
- Wheel alignment service
- Power steering repair
- Ball joint replacement
- Tie rod replacement
- Suspension inspection
Professional alignment for Highway 101 and local driving
Heating & Cooling Services
Stay comfortable year-round with our climate control services, essential for Sonoma County’s weather.
Services Include:
- Air conditioning repair and service
- Heater core replacement
- Radiator repair and replacement
- Coolant system flush
- Thermostat replacement
- Fan and belt service
Keep your family comfortable in any weather
Diagnostic Services
Our state-of-the-art diagnostic equipment quickly identifies problems, saving you time and money.
Services Include:
- Computer diagnostic scans
- Check engine light diagnosis
- Emissions testing support
- Pre-purchase inspections
- Vehicle health assessments
- Troubleshooting mysterious issues
Advanced diagnostics for accurate, efficient repairs
Preventative Maintenance Services
Keep your vehicle running reliably with regular maintenance – essential for Santa Rosa’s diverse driving conditions.
Oil Change & Filter Service
- Conventional, full synthetic, and high-mileage oils
- Filter replacement with every service
- Multi-point inspection included
- Quick 30-minute service
Fluid Services
- Transmission fluid replacement
- Brake fluid service
- Power steering fluid
- Coolant system flush
- Differential service
Tune-Up Services
- Spark plug replacement
- Air filter replacement
- Fuel filter service
- Ignition system service
- Restore performance and fuel economy
Battery & Charging System
- Battery testing and replacement
- Charging system diagnosis
- Alternator testing
- Free battery testing
Factory Scheduled Maintenance
- Follow manufacturer recommendations
- Maintain warranty coverage
- All makes and models
Specialized Services
Hybrid Vehicle Service
Expert service for Toyota Prius, Honda Insight, and all hybrid vehicles popular in Santa Rosa.
Luxury Vehicle Service
Specialized care for BMW, Mercedes-Benz, Audi, Lexus, and other luxury automobiles.
Fleet Vehicle Service
Commercial vehicle maintenance for Santa Rosa businesses and government agencies.
Pre-Purchase Inspections
Comprehensive vehicle inspections before you buy – protect your investment.
Why Choose On-Site Auto Repair for Your Service Needs?
Honest & Transparent
No upselling, just honest advice about what your car needs
State-of-the-Art Equipment
Latest diagnostic technology ensures accurate, efficient repairs.
Free Estimates
Know what you’re paying before any work begins.
Quality Parts & Warranty
Premium parts with warranty protection on all work.
ASE Certified Technicians
Our mechanics are trained and certified to work on all makes and models.
Honest, Transparent Service
No upselling – just honest advice about what your car needs.
Same-Day Service
Most repairs completed while you wait.
Convenient Location
Easy access from Highway 101 and all Santa Rosa neighborhoods.
Vehicles We Service
We service ALL makes and models, from daily drivers to luxury vehicles:
Popular Makes in Santa Rosa:
- Toyota & Lexus – Camry, Corolla, Prius, 4Runner, RX, ES
- Honda & Acura – Civic, Accord, CR-V, Pilot, TLX, MDX
- Ford – F-150, Explorer, Escape, Mustang, Focus
- Chevrolet – Silverado, Equinox, Malibu, Tahoe, Suburban
- Nissan & Infiniti – Altima, Sentra, Rogue, Pathfinder, Q50
- Subaru – Outback, Forester, Impreza, Legacy, Ascent
- Hyundai & Kia – Elantra, Sonata, Santa Fe, Optima, Sorento
- Volkswagen – Jetta, Passat, Tiguan, Atlas
- BMW & Mercedes – All series and models
- Jeep – Wrangler, Grand Cherokee, Compass, Cherokee
Don’t see your vehicle? We work on ALL makes and models!
Service Areas
Proudly serving Santa Rosa and surrounding Sonoma County communities:
Santa Rosa Neighborhoods:
- Railroad Square (our location)
- Bennett Valley
- Fountaingrove
- Roseland
- Southwest Santa Rosa
- Rincon Valley
- West End
- South Park
- Oakmont
- Coddingtown area
Surrounding Cities:
- Petaluma
- Sebastopol
- Windsor
- Rohnert Park
- Healdsburg
- Cotati
- Forestville
We’re your neighborhood auto repair experts, no matter where you live in Sonoma County!
Current Service Specials
FREE Services
- Free brake inspection – Complete brake system check
- Free battery testing – Check battery and charging system
- Free diagnostic scan – With any repair service
- Free estimates – All services, no obligation
Diagnostic Services
-
- $25 Off first service over $100 (new customers)
- $50 Off major repairs over $500
- Oil change special – Full synthetic $69.95
- 10% Off for seniors (65+) and military
Call (707) 326-8655 to schedule and mention these specials!
Emergency Auto Repair Services
Vehicle breakdown in Santa Rosa? We’re here to help!
Whether you’re stranded near Santa Rosa Plaza, broken down on Highway 101, or having trouble in any Santa Rosa neighborhood, call us immediately:
Emergency Line: (707) 326-8655
We provide emergency services for:
- Engine won’t start
- Overheating issues
- Brake problems
- Electrical failures
- Transmission problems
- Battery/charging issues
Fast response throughout Santa Rosa and Sonoma County
Schedule Your Service Today
Ready to experience the best auto repair service in Santa Rosa?
On-Site Auto Repair
363 W 9th St B & C
Santa Rosa, CA 95401
Historic Railroad Square district
Phone: (707) 326-8655
Email: info@on-siteautorepair.com
Business Hours:
- Monday – Friday: 8:00 AM – 5:30 PM
- Saturday: 8:00 AM – 4:00 PM
- Sunday: Closed
Scheduling Options:
- Call us at (707) 326-8655
- Stop by our shop in Railroad Square
- Email us for non-urgent service requests
We’re conveniently located near downtown Santa Rosa with easy access from Highway 101 and all Santa Rosa neighborhoods.
What Our Santa Rosa Customers Say
I’ve been bringing my cars to On-Site Auto for 5 years. They’re honest, fast, and their prices are fair. I wouldn’t trust my family’s vehicles to anyone else in Santa Rosa.
– David R., Bennett Valley
My Honda needed transmission work and I was worried about the cost. The team at On-Site gave me a fair estimate and completed the work quickly. Great service!
– Lisa K., Fountaingrove
Emergency brake repair when I was visiting Santa Rosa. They got me in immediately and had me back on the road the same day. Excellent service!
– Michael T., San Francisco (visiting Santa Rosa)
Frequently Asked Questions
Our certified mechanics answer the most common car repair questions to help you stay informed and confident. Explore our FAQs for honest, expert advice trusted by Santa Rosa drivers.
Do you provide loaner cars or shuttle service?
While we don't provide loaners, we're located in downtown Santa Rosa's Railroad Square with easy access to shopping, dining, and public transportation while you wait.
Can you work on my vehicle if it's still under warranty?
Absolutely! We perform warranty-compliant maintenance and repairs. We use OEM or equivalent parts to maintain your vehicle's warranty coverage.
How do I know if I really need the recommended service?
We provide detailed explanations and show you exactly what needs attention. We never pressure you into unnecessary repairs - our reputation depends on honest service.
Do you offer payment plans for major repairs?
We accept cash, check, and all major credit cards. For major repairs, we can discuss payment options that work for your budget.
What if my car breaks down outside of business hours?
Call our main number (707) 326-8655 and leave a message. We'll get back to you first thing in the morning to arrange service.
ReviewsWhat Our Clients Say
Brands We ServiceAuto Repair Brand
Toyota Repair
Honda Repair
Ford Repair
Chevrolet Repair
Nissan Repair
Mercedes Repair
Lexus Repair
Acura Repair
Infiniti Repair
Kia Repair
Hyundai Repair
Subaru Repair
Mazda Repair
Volkswagen Repair
Contact Info
Location
363 W 9th St B & C
Santa Rosa, CA 95401
Phone
707-326-8655
Hours
- Monday-Thursday: 7:30 AM - 4:30 PM
- Friday: 7:30 AM - 12:00 PM
- Saturday: Closed
- Sunday: Closed
New Customer Special:
$25 off your first service over $100. New customers only. One per household. Mention this offer when you call. Valid through December 31, 2026.
Oil Change Special:
Full synthetic oil change for $69.99. Includes up to 5 quarts of oil and a new oil filter. Most cars and light trucks. Valid through December 31, 2026.
Free Brake Inspection
Free brake inspection. We check pads, rotors, fluid, and lines and give you a written report. No purchase required.
Latest News
Why Is My Car Burning Oil So Fast in Healdsburg? What Excessive Oil Consumption Really Means
If you’re adding a quart of oil every few weeks in Healdsburg or anywhere in Sonoma County, something’s not right — and ignoring it can lead to serious engine damage. Here’s how to tell whether you have a real problem, what causes excessive oil consumption, and when it’s time to get your car looked at by a mechanic you can trust.
Why Is My Car Using More Gas Than Usual in Petaluma? What’s Behind Sudden Drops in Fuel Economy
If your car is suddenly getting fewer miles per gallon than it used to, something is wrong — and it’s rarely just the gas prices. Here’s what actually causes fuel economy to drop in Petaluma and across Sonoma County, and what you can do about it.
Why Is My Car Taking Forever to Warm Up in Rohnert Park? What a Slow-Warming Engine Actually Means
If your car is taking unusually long to reach normal operating temperature in Rohnert Park or anywhere in Sonoma County, it’s not just an inconvenience — it’s often a sign that your thermostat or cooling system needs attention. A slow-warming engine can hurt fuel economy, trigger the check engine light, and cause long-term engine wear. Here’s what’s actually going on and when to get it looked at.
Why Is My Subaru Using So Much Oil Between Changes in Sonoma County? What Subaru Owners Need to Know
If your Subaru is burning through oil faster than it should, you’re not alone — and it’s not something to ignore. Excessive oil consumption is one of the most common complaints from Subaru owners in Sonoma County, and understanding what’s behind it can save your engine. Here’s what’s actually going on and what to do about it.
Why Is My Car’s Heater Not Working in Sebastopol? What to Check Before Winter Gets Worse
If your car’s heater is blowing cold air or barely warming up during Sonoma County’s wet winters, it’s more than just a comfort issue — it can affect your defroster, visibility, and engine health. Here’s what’s likely going on and when to bring it in for a proper diagnosis.
How Do You Know If Your Car Needs a Wheel Alignment in Windsor or Santa Rosa?
If your car is pulling to one side, your steering wheel feels off-center, or your tires are wearing unevenly, you probably need a wheel alignment. Here’s how to recognize the signs, why Sonoma County roads are especially hard on alignment, and when to get it checked.
Why Is My Car Hesitating When I Accelerate in Santa Rosa? What’s Causing That Sluggish Response
If your car hesitates, stumbles, or feels sluggish when you press the gas pedal in Santa Rosa or anywhere in Sonoma County, something is off — and it’s usually more than just a minor annoyance. This article explains the most common causes of acceleration hesitation, what warning signs to watch for, and when it’s time to bring your vehicle in before a small problem turns into a costly repair.
Why Is My Car Making a Grinding Noise When I Turn in Petaluma? What’s Going On with Your CV Axles and Wheel Bearings
A grinding or clicking noise when you turn your steering wheel is one of those symptoms you shouldn’t ignore — it usually means your CV axles or wheel bearings are telling you something important. If you’re driving around Petaluma or anywhere in Sonoma County and noticing this sound, here’s what it actually means and when to get it checked.
Why Does My Car Smell Burning When I Drive in Sonoma County? What Different Smells Actually Mean
A burning smell coming from your car is never something to ignore — and different smells point to very different problems. Here’s how to identify what you’re smelling and what to do about it before a minor issue turns into a major repair.
Why Is My Car Leaking Fluid in Petaluma? How to Identify What’s Dripping Under Your Vehicle
A puddle under your car isn’t always serious — but it’s never something to ignore. This guide helps Petaluma and Sonoma County drivers identify common fluid leaks by color, location, and smell, and explains when it’s safe to drive and when you need to pull over immediately.
Read More About Our Auto Mechanic Services
On Site Auto Repair in Santa Rosa is a full service auto mechanic shop. Our auto mechanics are certified and are here to help with all of your repair needs. No auto repair job is too big or too small for On Site Auto Repair. We handle all types of auto repair, including regular maintenance, engine repair, brake work, and troubleshooting. If you are looking for honest and reliable auto mechanics, give us a call today. Ask us about our new customer specials.
Vehicles are usually described as 5 speed or 6 speed, meaning they have that many gear ratios. Those gears let the vehicle travel across the full range of speeds and use the engine's power efficiently. Transmissions are complex and are in constant use, so they take a lot of wear and tear. Many owners also forget to check and change the fluid on a regular schedule. That is why transmission problems are so common. At On Site Auto Repair in Santa Rosa, our transmission technicians can diagnose, repair, or replace your transmission. If you are looking for an honest transmission repair shop, give us a call today.
There are several warning signs that your vehicle can give you before your brakes may reach the point of potential failure or extensive repair. Whether composed of ceramic, semi-metallic, or organic materials, brake pads erode each time you depress the brake pedal. If the pads wear down too much without being replaced, the metal housing for the pads will make contact with the metal rotors (or drums), which may produce not only a safety issue but a situation where the rotors/drums are required to be replaced as a result of the prolonged contact of metal parts without the pad buffer. If you are in need of an affordable brake repair mechanic in Santa Rosa, please do not hesitate to schedule an appointment today!
Vehicle Inspection In Santa Rosa
The key to top notch automotive repair and troubleshooting lies in a thorough understanding of what’s actually going on under the hood. Sure, you know that a radiator keeps your engine cool, but understanding how it keeps it cool is the key to solving technical problems efficiently. If you know which parts perform what function, your powers of diagnosis will be much more powerful.
Radiator Inspection Service In Santa Rosa
Ensuring that your vehicle’s engine cooling system is in proper operating condition is extremely essential to engine life and performance. Operating at excessive temperatures can lead to premature engine wear. Your vehicle’s engine cooling system should be checked periodically, and a radiator coolant flush is also recommended to prohibit radiator corrosion. On Site Auto Repair will thoroughly drain and power flush the old coolant and particulates, and refill the cooling system with your vehicle manufacturer’s recommended coolant.
Our Santa Rosa Service Area – Directions to On Site Auto
Proudly serving drivers throughout Santa Rosa neighborhoods, from Railroad Square to Bennett Valley, and extending our trusted auto repair services to Petaluma, Sebastopol, Windsor, and all of Sonoma County.
Auto Repair Services We Offer in Santa Rosa, CA
Our shop at 363 W 9th St B & C handles a wide range of repairs and maintenance for drivers across Santa Rosa and Sonoma County.
Engine Diagnostics and Check Engine Light
A check engine light means your car is reporting a fault. We connect an OBD-II scanner, read the fault codes, and explain what they mean in plain language. We diagnose the problem first, then tell you what the repair will cost.
Oil Change Service
We do full-synthetic and conventional oil changes. We use the viscosity grade your manufacturer specifies, such as 5W-30, 5W-20, or 0W-20, and we replace the oil filter every time.
Brake Repair and Replacement
Worn brake pads squeak. Worn rotors grind. A soft brake pedal is a warning. We inspect and replace brake pads, rotors, and calipers using OEM-quality and aftermarket parts, depending on your budget.
Battery, Alternator, and Starter Repair
We test your battery with a load tester, not just a voltage check. We also test the alternator and starter, because a failing alternator will kill a new battery quickly.
AC and Heating Repair
If your AC is not blowing cold, we recharge the refrigerant and check for leaks. If your heat is not working, we diagnose the cause and repair it.
Scheduled Maintenance and Tune-Ups
We handle spark plug replacement, belt inspection and replacement, air and cabin filter replacement, fuel system service, coolant flushes, and transmission fluid service. If you are not sure what your car is due for, we look it up by make, model, and mileage.
Tire Rotation and Inspection
Uneven tire wear affects handling, fuel economy, and tire life. We rotate your tires, measure tread depth, inspect the sidewalls, and check the pressure.
Pre-Purchase Inspection
Thinking about buying a used car? We check the brakes, belts, fluids, undercarriage, and suspension, and we run a diagnostic scan for hidden fault codes. Call for current pricing.
Why Santa Rosa Drivers Choose On Site Auto Repair
Free estimates. You know the cost before we start any work.
Same-day appointments available. Call and we will tell you what we can fit in today.
ASE Certified mechanics. Credentialed professionals with real diagnostic tools.
Convenient location. We are in Railroad Square, minutes from downtown Santa Rosa, with shops and restaurants in walking distance while you wait.
Ready to Book?
Call (707) 326-8655 or send us a message with your vehicle and what is going on with it. We will give you a free estimate before we schedule anything.
On Site Auto Repair — 363 W 9th St B & C, Santa Rosa, CA 95401. Serving Santa Rosa, Petaluma, Rohnert Park, Sebastopol, Windsor, Healdsburg, and Sonoma County.
Things To Do In Santa Rosa, CA
From exploring the Charles M. Schulz Museum and Luther Burbank Home & Gardens to enjoying outdoor adventures at Spring Lake Regional Park and Annadel State Park, Santa Rosa offers endless opportunities for family fun, Wine Country experiences, and recreational activities that keep our community vibrant year-round.
Santa Rosa Transportation to On-Site Auto Repair
Conveniently located in the historic Railroad Square district with easy access from Highway 101, our auto repair shop is just minutes from downtown Santa Rosa, Santa Rosa Plaza, and all major neighborhoods, with nearby public transit options and walkable access to local shops and restaurants while your vehicle is being serviced.
Contact On-Site Auto Repair Today
Ready to experience honest, reliable auto repair in Santa Rosa?
Whether you’re dealing with a check engine light, need routine maintenance, or facing an unexpected breakdown, our ASE-certified mechanics are here to help. We serve drivers throughout Santa Rosa and Sonoma County with the same commitment to quality and honesty that has made us the area’s most trusted auto repair shop.