What Is Dyno Smog Testing and Why Older Cars Need It

October 31, 2025

If you drive a vehicle made before the year 2000, you’ve probably heard about something called a dyno smog test or BAR-97 test.

At Jim Brangham Auto Repair, we perform this type of smog testing to make sure older vehicles meet California’s emissions standards. Plus, it keeps your vehicle running clean and reliable.

What Is a Dyno Smog Test?

A dyno smog test checks how much pollution your car gives off while it’s actually running under real driving conditions. Your vehicle’s drive wheels are placed on a machine called a dynamometer, which lets your car “drive” in place. While your car runs through different speeds and loads, the system measures the exhaust gases coming out of the tailpipe.

This process is part of the BAR-97 smog testing system. This is required by the California Bureau of Automotive Repair (BAR) for most vehicles built before the 2000 model year.

Why Newer Cars Don’t Need It

Cars built after 2000 have advanced onboard computers (OBD-II systems) that monitor emissions automatically. For those vehicles, smog checks are done by plugging into the car’s computer. But older vehicles don’t have that same technology—so dyno testing helps simulate real driving to get accurate readings.

What We Look For During Testing

During a BAR-97 dyno smog test, our certified technicians measure:

Carbon monoxide (CO)
Hydrocarbons (HC)
Nitrogen oxides (NOx)

If any of these levels are too high, your car may fail the test. But don’t worry—our team can help identify the cause, perform the needed repairs, and retest your vehicle to make sure it passes.

Keep Your Classic or Older Car Legal and Reliable

Passing your smog test isn’t just about staying legal—it’s also about keeping your car in top shape. A properly running engine burns fuel efficiently, saves gas, and helps protect our air quality here in Cathedral City and across California’s Coachella Valley.

Schedule Your BAR-97 Smog Test Today

If your car is older than a 2000 model year, it likely requires a BAR-97 dyno smog test. At Jim Brangham Auto Repair, we’re a STAR Certified Smog Check Station, and our team has the training and equipment to get your vehicle tested quickly and accurately.

✅ Call us today at (760) 321-7040 or click the Book Service button to schedule your dyno smog test and keep your car running clean and compliant.

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Understanding Auto Diagnostics: A Guide from Jim Brangham Auto Repair

By Jim Brangham Auto Repair • November 3, 2025

Discover expert auto diagnostics at Jim Brangham Auto Repair in Cathedral City, CA. Enhance vehicle performance today! Schedule an online appointment now.

Why Your Power Steering Pump Is So Important

October 28, 2025

When your power steering is working right, turning the wheel feels effortless. But if your wheel feels stiff or you hear a whining sound when turning, you may have low fluid or a worn-out pump. Why Low Power Steering Fluid Is Dangerous Driving with low or no power steering fluid can be unsafe. The pump needs that fluid to build pressure and help you steer. Without it, your wheel can become very hard to turn—especially when parking or driving slowly. That can make it harder to control your car in an emergency. Low fluid also causes damage inside the pump, since the fluid keeps it cool and lubricated. If the pump runs dry, it can wear out fast or even stop working completely. What could’ve been a small fix can turn into a much more expensive repair. The Difference with Electronic Power Steering Many newer vehicles use electronic power steering (EPS) instead of hydraulic. EPS uses an electric motor to help turn the wheels. These systems don’t need fluid and are more fuel efficient. Still, it’s important to have them checked now and then to make sure the sensors and motor are working correctly. Keep Your Steering Safe and Smooth No matter what kind of steering system your vehicle has, regular checks are important. If you notice stiff steering, whining noises, or see fluid under your car, don’t ignore it. At Jim Brangham Auto Repair in Cathedral City, CA , our ASE-certified team can inspect your power steering system, top off or replace the fluid if needed, and make sure everything is safe and working properly. Call Jim Brangham Auto Repair today at (760) 321-7040 to schedule your power steering inspection and service in Cathedral City, CA. We’ll help keep your car steering smoothly and safely for miles to come.

Why Differential Service Can Save You Money

October 16, 2025

What the Differential Does The differential is what helps your wheels turn smoothly when you go around corners. It lets each wheel move at a slightly different speed, which makes driving easier and safer. If your differential starts to wear out, you might hear grinding or whining sounds, or feel your car handle differently. It’s one of those parts you don’t think about until something goes wrong — and by then, it can get expensive to fix. Why Differential Fluid Service Is Important Inside your differential is fluid that keeps the gears cool and lubricated. Over time, that fluid breaks down from heat, friction, and dust — especially in California’s desert weather. When the fluid gets dirty, it can’t protect the parts anymore. If that happens, it can cause: Rough or noisy driving Gear damage Leaks or vibration Costly repairs down the road That’s why changing your differential fluid on time is so important. It’s a simple and affordable way to keep your car running smoothly. How Often Should You Change It? Most cars need differential service every 30,000 to 60,000 miles. If you tow, haul heavy loads, or drive in hot weather often, you might need it sooner. The good news? It’s quick, easy, and saves you a lot of money compared to replacing the whole differential. How It Saves You Money Fresh differential fluid reduces wear and helps prevent breakdowns. A full differential replacement can cost thousands, while a fluid service is just a small routine maintenance. Taking care of it early keeps your car safe and reliable — and helps your budget in the long run. Trust Jim Brangham Auto Repair At Jim Brangham Auto Repair, our ASE-certified team knows how to keep your car in top shape. We offer differential service, A/C repair, smog inspections, and more to help your vehicle last longer and run better. If your car feels different while turning, or it’s been a while since your last service, come see us today. We’ll make sure your differential — and the rest of your car — gets the care it deserves. Call Jim Brangham Auto Repair at (760)321-7040 in Cathedral City today for honest, expert car care you can trust!