Welcome to On Site Auto Repair!
About On Site Auto Repair in Santa Rosa, CA
Trusted Since 2011 — Local Experts You Can Count On
At On-Site Auto Repair, we take pride in offering honest, skilled auto repair backed by decades of hands-on experience. As a family-owned shop in Santa Rosa, we treat every customer like a neighbor and every car like our own.
Serving Santa Rosa Since 2011
★★★★★ 4.9/5 (117 Google Reviews)
Your Local Auto Repair Experts & Reliable Repairs
On Site Auto – Auto Repair Service in Santa Rosa, CA
At On Site Auto Repair, we take pride in delivering expert auto repair services with integrity and precision. Our certified mechanics have years of hands-on experience and are committed to keeping your vehicle running smoothly. Whether it’s brake repairs, transmission work, or routine maintenance, we treat every car like it’s our own. As a locally owned and operated shop in Santa Rosa, we’re here to serve our community with honest diagnostics, transparent pricing, and fast, dependable service. When you choose us, you’re not just a customer—you’re part of the On Site Auto Repair family.
A Team You Can Trust
Our team is made up of ASE-certified technicians who are passionate about cars and dedicated to honest, accurate service. Whether you’re driving an everyday commuter, a classic car, or a light-duty truck, we bring the same level of precision and care to every job—big or small.
We believe in doing the job right the first time, using the latest diagnostic tools and quality parts to ensure lasting results. From brake repairs and oil changes to engine diagnostics, suspension work, and full transmission service, we’ve got you covered.
Visit us at 363 W 9th St B & C, Santa Rosa, CA 95401
Call us today at (707) 326-8655 to schedule your next 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 Are My Tires Wearing Unevenly in Cotati? What Sonoma County Drivers Need to Know About Tire Wear Patterns
Uneven tire wear is more than a cosmetic issue — it’s usually a sign that something mechanical is off with your vehicle. If you’re driving in Cotati, Rohnert Park, or anywhere in Sonoma County and noticing bald edges, center wear, or cupping on your tires, here’s what’s actually causing it and what to do about it.
Why Is My Car’s Water Pump Failing in Sebastopol? What Sonoma County Drivers Need to Know
A failing water pump is one of the most overlooked causes of engine overheating in Sonoma County. If you’re driving in Sebastopol or anywhere around West County, here’s how to spot the warning signs before a small problem turns into a very expensive repair.
Why Are My Shocks and Struts Wearing Out So Fast in Sonoma County? What Drivers in Healdsburg and Surrounding Areas Need to Know
If your car feels bouncy, pulls on curves, or clunks over bumps on Sonoma County’s back roads, your shocks and struts may be telling you something important. Here’s what accelerates wear in this region, how to recognize the signs, and when it’s time to get them replaced.
Why Is My Car’s Brake Fluid Dark or Contaminated in Windsor? What Sonoma County Drivers Need to Know About Brake Fluid Service
Brake fluid doesn’t last forever — and in Sonoma County’s hilly terrain, contaminated fluid can quietly undermine your stopping power before you ever notice a problem. Here’s what dark or dirty brake fluid actually means, why it matters more than most drivers realize, and when to get it serviced in Windsor or anywhere across the North Bay.
Why Is My Car’s Clutch Slipping or Hard to Press in Santa Rosa? What Manual Transmission Drivers Need to Know
A slipping clutch or a pedal that suddenly feels stiff and heavy isn’t something to put off — it usually means your clutch system is wearing out or has a hydraulic problem. Here’s what manual transmission drivers in Santa Rosa and Sonoma County should watch for, and when it’s time to get it checked.
Why Is My Car’s Serpentine Belt Squealing or Cracking in Rohnert Park? What Sonoma County Drivers Need to Know
That squealing noise coming from under your hood in Rohnert Park isn’t something to ignore — it’s often your serpentine belt telling you it’s on borrowed time. Here’s what the belt actually does, how to spot the warning signs, and when to get it replaced before it leaves you stranded.
Why Is My Car’s AC Blowing Warm Air in Petaluma? What’s Really Going On with Your Cooling System
If your car’s AC is blowing warm air in Petaluma or anywhere in Sonoma County, it’s usually one of a handful of fixable problems — not an automatic reason to panic. This guide walks you through the most common causes, what to listen and look for, and when it’s time to bring your vehicle in for a proper diagnosis.
Why Is My Check Engine Light On in Healdsburg? What That Warning Light Is Actually Trying to Tell You
If your check engine light just came on somewhere between Healdsburg and Santa Rosa, don’t panic — but don’t ignore it either. That little amber light can mean anything from a loose gas cap to a misfiring engine, and knowing how to tell the difference can save you from a costly breakdown. Here’s what Sonoma County drivers actually need to know.
Why Is My Car’s Fuel Injector Clogged or Failing in Rohnert Park? What Sonoma County Drivers Need to Know
If your car is running rough, struggling to start, or suddenly getting worse gas mileage, dirty or failing fuel injectors might be the cause. Here’s what Rohnert Park and Sonoma County drivers need to know about fuel injector problems, what they actually feel like to drive, and when it’s time to bring your vehicle in.
Why Is My Car’s Alternator Failing in Sonoma? What Drivers in the Valley Need to Know About Charging System Problems
If your car’s lights are dimming, your battery keeps dying, or you’re hearing a whining noise under the hood, your alternator might be the real culprit. Drivers in Sonoma and throughout Sonoma Valley often confuse alternator problems with battery issues — here’s how to tell the difference and what to do about it.
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.
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.
We Service Clients From All Over Sonoma County
From Wine Country commuters to local families, we provide reliable auto repair services to Santa Rosa, Petaluma, Sebastopol, Rohnert Park, Windsor, Healdsburg, and communities throughout 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.