Engine Diagnostics

Professional Engine Diagnostics & Repair in Rancho Santa Margarita, CA

Engine issues don’t wait for the right time, so when something feels off, you need a shop that’s ready to respond. At Bobby Grich Auto Repair, we bring big-league focus to every check engine light, rough idle, or misfire. With advanced diagnostics, ASE-certified expertise, and a lifetime warranty on all repairs, we deliver the answers and the peace of mind you’ve been looking for.

Know When It’s Time for Engine Repair

Modern engines are smart, but when something’s off, they rely on you to take action. That’s where we come in. Ignoring engine issues can lead to performance loss, poor fuel economy, or even major damage. That’s why it’s important to act early and get a clear diagnosis from professionals who know what to look for.

We help with issues like:

Check engine light diagnosis
Engine misfires or rough running
Stalling or hesitation
Poor fuel efficiency
Unusual noises or smells from under the hood
Hard-starting or no-start conditions
Battery drain or warning lights

If your vehicle isn’t driving like it used to, don’t wait. Our team is here to help you get answers fast.

Our Expert Engine Services, Start to Finish

When it comes to engine diagnostics and repair, we leave nothing to guesswork. We perform in-depth inspections using the latest diagnostic tools and back every repair with transparent explanations and real solutions. Here’s what we offer:

Engine Diagnostics

Using factory-level diagnostic scanners and live data monitoring, we track down check engine light causes, drivability concerns, sensor issues, and electrical malfunctions. You’ll get a clear explanation of the problem, and a plan to fix it right.

Misfire Diagnostic & Repair

Misfires can cause jerking, poor acceleration, and long-term engine damage. We test ignition coils, plugs, fuel injectors, and cylinder compression to isolate the issue and correct it, restoring power and efficiency while preventing further wear.

Engine Tune-Ups

If your vehicle is lagging or idling rough, it may be time for a tune-up. We replace worn spark plugs, inspect ignition components, and make targeted adjustments to help your engine run cleaner, stronger, and more efficiently.

Starting & Charging System Repair

If your engine struggles to turn over or you’re experiencing battery drain, we test and repair the full starting and charging system, including batteries, alternators, starters, fuses, and wiring, to ensure reliable, consistent power every time.

Battery Replacement

A weak or failing battery can leave you stranded. We perform voltage tests, check for internal resistance and terminal corrosion, and install top-tier replacements that match your vehicle’s specs for longevity and reliability.

Fuel System Repair

Poor fuel delivery leads to hesitation, low power, and reduced mileage. We clean or replace fuel injectors, swap clogged filters, and test fuel pressure to ensure optimal combustion and smooth, balanced performance.

Exhaust System Diagnostics

Exhaust system problems affect both performance and emissions. We inspect for leaks, damaged catalytic converters, faulty O2 sensors, and backpressure issues, resolving anything that compromises airflow or triggers dashboard lights.

Cooling System & Overheating Repairs

Engines run best within a narrow temperature range. We diagnose overheating and coolant loss, replacing water pumps, thermostats and hoses to restore proper cooling and protect against internal engine damage.

Gasket & Seal Repairs

Even small oil or coolant leaks can lead to big problems. We repair or replace valve cover gaskets, intake manifold gaskets, timing cover seals, and other components to prevent leaks, maintain fluid levels, and extend engine life.

Built to Last, Backed for Life

Not many shops back their work like we do. Our lifetime warranty on parts and labor sets us apart, giving you total confidence in every service. We also partner with extended warranty companies so you’re always covered.

Honest Work Under the Hood, Backed by a Name You Trust

When your engine needs attention, you deserve a team that treats your vehicle with purpose, not pressure. Here’s what makes us different:

Legendary Standards, Local Service: Inspired by Bobby Grich’s legacy of grit and excellence, we bring that same mindset to every repair—focused, precise, and always customer-first.

Honest Communication, Always: You’ll get straight talk about what your vehicle needs and why.

Certified Expertise: Our ASE-certified technicians diagnose and repair engine issues with skill, efficiency, and years of hands-on experience.

Clean Shop, Lifetime Promise: Our baseball-inspired shop is clean, comfortable, and every service includes a lifetime warranty on parts and labor.

Technology That Gets It Right: We use modern diagnostic tools and up-to-date software to identify the problem accurately.

Early Bird Drop-Off

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frequently asked questions

What are your business hours?

We are open Monday – Friday from 7:00 AM to 5:00 PM and Saturday 8:00 AM to 5:00 PM . Our flexible hours make it easy to get expert auto repairs at a time that works for you.

Where are you located?

You can find us at 28622 Oso Parkway, Suite A, Rancho Santa Margarita, CA 92688. Our shop is conveniently located for local drivers needing reliable auto care and a new shop opening soon.

What types of vehicles do you work on?

We service all makes and models, including domestic, European, Asian, and electric vehicles like Tesla. Our ASE-certified technicians have the expertise to handle everything from routine maintenance to complex repairs.

Can I book an appointment online?

Yes! Booking an appointment online is fast and easy, allowing you to schedule service at your convenience. However, we also welcome walk-ins and same-day service whenever possible.

Is this a cost-effective alternative to the dealership?

Absolutely! We offer dealership-quality repairs at fair, transparent prices, using high-quality parts backed by a lifetime warranty. Our expert service ensures the same level of care without the high costs.

Do you offer any discounts?

Yes, we offer military, first responder discount, AAA discount throughout the year. Please check our Coupons page for the latest promotions and savings on your next service.

Can I check on the status of my car at the shop?

Yes, you can contact us anytime for an update on your vehicle’s repair status. Our team ensures clear communication so you know exactly when your car will be ready.

Do you offer a warranty on repairs?

Yes! At Bobby Grich Auto Repair, we stand behind our work with a lifetime warranty on parts and labor, ensuring long-term reliability and peace of mind. Additionally, as a Technet-affiliated shop, our lifetime warranty is honored nationwide, so you’re covered wherever the road takes you

what our customers say about us

Get Back on the Road. Schedule Engine Service Today

When your engine isn’t performing like it should, bring it to a team that knows how to get things right. Bobby Grich Auto Repair combines sharp diagnostics, honest feedback, and skilled repair all under one roof.

We’re located at 28622 Oso Pkwy Suite A, Rancho Santa Margarita, CA 92688. Call or text us at (949) 709-8007 or book your appointment online.

Proudly trusted by drivers in Rancho Santa Margarita and communities across Orange County. Legends on the field, experts in the shop.