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A father-and-son mechanic duo flagged a surprising issue on a 2023 Mazda CX-5\u2014the kind of problem they say they\u2019re seeing more often, even on newer cars.<\/p>\n
Royalty Auto Service (@royaltyautoservice), which bills itself as a team trying to bring more transparency to car repair, explained that it took them a minute to nail down what was wrong because the Mazda was so new. They weren\u2019t expecting trouble on a car that fresh off the lot.<\/p>\n
The SUV already had serious mileage\u201496,588\u2014but the mechanics suggest the issue they uncovered shouldn\u2019t be happening this soon.<\/p>\n
As of this writing, their clip has pulled in more than 113,200 views.<\/p>\n
In the on-screen caption, the shop warned, \u201cThis Mazda is only 2 years old & is already having this problem! This is becoming more common every year!\u201d<\/p>\n
They doubled down in the video.<\/p>\n
\u201cThis is becoming a big problem on a lot of vehicles,\u201d one of them said, noting again that the Mazda \u201cdoes not sit still for long\u201d with nearly 100,000 miles on the odometer.<\/p>\n
He pointed out that the long-term fuel trims were maxed. The car was \u201cstuck at 25%.\u201d Everything else in the data looked normal\u2014until they got to the source of the issue.<\/p>\n
The fuel injectors were completely black.<\/p>\n
\u201cThere\u2019s some carbon buildup on there,\u201d the mechanic explained, adding that they tried cleaning the injectors and \u201cit didn\u2019t help.\u201d<\/p>\n
\u201cThis is not uncommon,\u201d he said, noting they\u2019d seen the same thing happen to a Ford just a few weeks earlier.<\/p>\n
His advice was straightforward: \u201cIf you\u2019re not running top-tier fuel, you need to run it.\u201d And while the mileage on the Mazda didn\u2019t help, he said the fix<\/a> for this kind of buildup isn\u2019t cheap.<\/p>\n When the mechanic says the long-term fuel trim is \u201cmaxed out,\u201d he\u2019s essentially saying<\/a> that the engine is getting too much air and not enough fuel, so the computer keeps trying to add more fuel<\/a> to even things out. Once it reaches 25%, that\u2019s typically the most it can give.<\/p>\n And that\u2019s where the gas comes in.<\/p>\n Using cheaper fuel can absolutely<\/a> make this worse. According to Cars.com<\/em>, top-tier gas contains extra cleaning additives<\/a> that help keep the fuel injectors inside the engine from getting dirty. Those injectors are what spray fuel into the engine, and they have tiny openings. When you use lower-quality gas that contains fewer detergents, those openings start to clog over time.<\/p>\n Once the injectors get clogged, they can\u2019t spray enough fuel<\/a>. That makes the engine run \u201clean,\u201d which means<\/a> there\u2019s too much air and not enough fuel. The car\u2019s computer sees this happening and tries to help by adding more and more fuel. That\u2019s what pushes the trim number all the way up to 25%.<\/p>\n Put simply, your engine needs to take in air and fuel simultaneously to run smoothly, but dirty injectors make it drink less. That\u2019s where top-tier fuel comes in. The extra cleaners in it help keep your car\u2019s injectors from gunking up in the first place, so the engine never gets pushed to that breaking point.<\/p>\n According to CarParts.com<\/a><\/em>, fuel injectors can last the life of your vehicle with proper maintenance or 50,000\u2013100,000 miles on average.<\/p>\n The site notes that experts recommend cleaning them every 25,000\u201330,000 miles.<\/p>\n That said, it adds, \u201cNote, however, that most vehicle owners never have their injectors cleaned and never need to replace a single one for hundreds of thousands of miles. Injector technology has greatly improved since the 1980s.\u201d<\/p>\n If you want to keep your injectors clean, Cars.com<\/a><\/em> states that top tier fuel (and the occasional fuel-injector cleaner if you don\u2019t always use top tier fuel) should be enough. If you intend to use an additive, make sure to check your owner\u2019s manual first, as some manufacturers advise against this.<\/p>\n Unlike tires or air filters, fuel injectors are not parts you need to change routinely. CarParts.com<\/em> states that you generally only need to replace them if they fail.<\/p>\n Viewers who watched @royaltyautoservice\u2019s clip were quick to blame cheap gas for the Mazda drivers\u2019 problem. While we can\u2019t say for certain that top-tier fuel would have prevented this specific issue, studies show<\/a> that using higher-quality gas is better for your car overall. There are dozens of brands that sell top tier fuel.<\/p>\n \u201cDefinitely cheap gas,\u201d one user said. \u201cI recommend and do it to my own vehicles, run fuel system cleaner thru the tank once a month. 44k, gumout, seaform, anything\u2019s better than replacing those fuel injectors.\u201d<\/p>\n Another added, \u201cPeople don\u2019t understand if your car is turbo, you must use premium gas. 91 or 93.\u201d<\/p>\n \u201cI always use top tier fuel,\u201d a third user chimed in. \u201cI\u2019ll pay the higher price rather than pay the price.\u201d<\/p>\n Some commenters even offered tips on where to find top tier gas. \u201cCostco sells top tier regular and premium gas, I think,\u201d one noted.<\/p>\nWhy Is the Fuel Trim Maxed Out?\u00a0<\/h2>\n
How Long Should Fuel Injectors Last?<\/h2>\n
Viewers Blame Cheap Gas For Mazda Driver\u2019s Problem<\/h2>\n