A simple Chevy error code could prevent engine damage and save you thousands — if you catch it in time

A Chevrolet Cruze remains one of the most beloved cars in the U.S. But a common error code that has been plaguing the 2014 model specifically has been a thorn in owners’ flesh for years — luckily, a TikTok mechanic has finally educated drivers once and for all.

It’s hard to be on a road anywhere in the world without seeing the 2014 Chevy Cruze, but that model is more popular than most people realize. In 2014 alone, it sold over 250,000 units and was one of the best-selling cars in North America. By 2019, when they finally stopped selling the model, almost 1 million units had been sold in the U.S. and Canada alone. Of course, those were different times, when incentives like free trade agreements were still firmly in place.

When cars flood the market like this, you usually get mechanics who have more than enough practice working on them, and sometimes even a quick glance can help them accurately assess what is plaguing your car. A mechanic with a TikTok account called Quality Auto Repair (@qualityautorepairredding) posted a video discussing the much-debated code P0171, more commonly known as the “lean code.”

The page pointed out that they know a lot of people have problems with it at their auto shop in Redding, California. One user commented, “I have seen the nub of that little orange diaphragm still plugged into that intake and then the rest of the diaphragm was missing so watch out for that.” Another user offered their experience on what else could be wrong, writing, “Another big one is the turbo bypass valve. The diaphragm splits or gets brittle. Gives an intermittent lean code. Just done one. GM part is very expensive. Go performance part instead for less.”

On its own, a P0171 error code means the engine is running “too lean,” which basically means the fuel mixture has too much air in it. The ratio is off, with too little fuel in the mix. Oftentimes, the issue ends up being worn-out spark plugs, a faulty oxygen sensor, or sometimes a defective mass air flow sensor. There are a couple of ways you can end up with a lean code.

The first fix is actually something you can check at home. The dipstick tube or the oil fill cap can sometimes be improperly fitted, and simply adjusting or securing them can make the error disappear from your dashboard.

But sometimes there are more advanced cases, and you would have to go to a mechanic. The Positive Crankcase Ventilation (PCV) system can sometimes develop a crack — as the mechanic suggested on TikTok — and that can allow air to leak into the system.

If you ignore it, your engine could start knocking, and you might eventually need a full replacement. So if that code shows up, you’d better take it with the utmost seriousness. Many owners of the 2014 Chevy Cruze end up ignoring the code and later complain that the car is “junk,” often comparing it to more durable brands like Toyota.

But as they say — if you don’t immediately fix a puncture, you might end up needing a new tire.