A father-and-son team at Royalty Auto Service found a big problem on a 2023 Mazda CX-5. The mechanics said they didn’t expect to see this kind of failure on such a new car. The Mazda had 96,588 miles in just two years, which is a lot. But the team said the problem they found shouldn’t happen this fast, even with high mileage.
According to Motor1, Royalty Auto Service warned on their TikTok video that this issue is getting more common. They said in their video, “This Mazda is only 2 years old & is already having this problem! This is becoming more common every year!” One mechanic said this is “becoming a big problem on a lot of vehicles.”
The diagnosis showed the long-term fuel trims were maxed out at 25%. Everything else looked normal. But when they checked the actual parts, they found the real issue. The fuel injectors were completely black with carbon buildup. They tried cleaning them, but “it didn’t help.” The owner now faces an expensive repair.
Cheap gas is ruining engines faster than ever
When fuel trim maxes out at 25%, it means the engine is getting too much air and not enough fuel. The car’s computer tries to fix this by adding more fuel, but it can only go up to 25%.
This problem comes from using cheap gas. Fuel injectors spray fuel into the engine through tiny openings. When you use lower-quality gas without cleaning detergents, those openings get clogged over time. Once they’re blocked, the injectors can’t spray enough fuel. The engine runs lean, and the computer pushes the fuel trim to the maximum to try to fix it.
The mechanic’s advice is simple. He said, “If you’re not running top-tier fuel, you need to run it.” Top-tier gas has extra cleaning additives that keep fuel injectors clean and prevent buildup. Experts also warn that common driving habits cost thousands in repairs when drivers aren’t careful.
The average lifespan for fuel injectors is 50,000 to 100,000 miles. With good maintenance, they can last much longer. Experts say to clean them every 25,000 to 30,000 miles. You don’t change them regularly like air filters unless they fail.
The video got over 113,200 views. Many viewers were shocked by the mileage. The average car only drives 10,000 to 12,000 miles per year. This Mazda had almost 97,000 miles in two years. One viewer said: “100k miles in 2 years!!!! My dad has a 2022 Toyota Highlander and only has 13,000 miles!”
Most viewers blamed cheap gas for the problem. One user said, “People don’t understand if your car is turbo you must use premium gas 91 or 93.” Another said, “I always use top tier fuel. I’ll pay the higher price rather than pay the price.”
Some mechanics have even explained how topping off at the gas pump can lead to expensive consequences. Studies show that higher-quality gas is better for your car. This Mazda’s black injectors prove that cheap gas costs you more later.
Published: Dec 4, 2025 03:05 pm