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Fuel Injectors: Why Do They Matter?

Most of us only think about things like fuel injection systems when we have to, and even then, we’d prefer not to. And why not? It’s like speaking a different language. Most of us want to step on the gas and go, not worry about what makes the car run. Our idea of high maintenance is what fuel to add and where we can get it the cheapest. 

When it comes to fuel injection systems, it’s typical to have more questions than answers. That’s okay. We know cars. Louie and John’s Complete Auto Service is always happy to Help you resolve your car issues. 

Here are some frequently asked fuel injection questions:

Why Does An Engine Have Fuel Injectors? 

If you drive an older car, it probably has a carburetor. Still, most cars built since the 1980s have more effective devices, called injectors, that spray fuel to be combined with air and lit with a spark inside the engine.

Older fuel injectors spray fuel into the intake manifold, where the fuel mixes with air and then enters the combustion chamber. Newer fuel injectors use “direct injection” into the cylinder itself, which is more efficient.  

Does It Matter If They Are Clean?

As you drive for thousands of miles, the gasoline you use causes deposits to accumulate in the injectors. All gas now contains some detergent to prevent accumulation, but not all gas brands have the exact amounts or types of detergent. A Consumer Reports article describes how gas from “Top Tier” stations includes better detergent, which can help keep your injectors cleaner.  

Since nothing lasts forever, the fuel injectors in your car’s engine eventually stop performing well, and your engine won’t work as it should. The fuel might be injected at the wrong time, or in the wrong amount – or not at all. 

How Will You Know If They Need Cleaning? 

Unless you are familiar with the inner workings of the car and experienced in car repair and prevention, then you probably do what most of us do: you take the car to the shop, and they figure out what’s wrong. Even so, it helps to have some degree of knowledge, so your car doesn’t catch you by surprise. 

Of course, the symptoms of faulty fuel injectors sometimes mimic other issues, but here are some signs to watch out for:

  • Your engine vibrates, runs rough, or even stalls.
  • It might not accelerate like it should – or may instead surge when it shouldn’t. 
  • You might have a fuel leak and may even be able to smell fuel.
  • Your gas economy (miles per gallon) may drop.
  • You might even get the dreaded “CHECK ENGINE” light.
  • And be aware – if you run out of gas, impurities in the tank can be pushed through the fuel filter and into your injectors, clogging them.  

The good news is that replacing your fuel injection system isn’t always necessary. Sometimes cleaning is much cheaper.

Is It Dangerous To Drive With Faulty Fuel Injectors? 

The answer to that is, “It depends.” 

How severe are the symptoms, and how do you know when it’s crossed the line from annoying to hazardous? 

Are you having just a little trouble with roughness, or can you smell fuel leaking? Has your mileage gone from 35 mpg to 25 mpg? Is your car stalling at every traffic light? Or does your engine quit as you drive on the highway? 

There are times when the judgment of a professional is necessary. Unless you are an expert at detecting engine problems, you’ll want to take your vehicle to people who know what the problem is and how to fix it.

What’s The Best Way To Clean Fuel Injectors?

These days, fuel injection system cleanings happen with in-line service machines and chemical cleaning solutions. New doesn’t always equate to LESS care – quite the opposite. Modern cars need more maintenance.

If your fuel injectors have heavy deposits (they’re gunked up), your system should be drained and at least partly disassembled to allow a cleaner to pass through the injectors with special equipment. When this is performed by a professional shop, your engine’s performance is significantly improved.  

While situations vary, a professional auto mechanic has the training to detect whether the system should be replaced or cleaned and which method garners the best results. 

At Complete Auto Repair of Ann Arbor, your car problem is our solution.  

“Complete auto repair.” Only the best can make a bold statement like that. At Louie and John’s, we employ only the most qualified certified mechanics. We take pride in our artistry. Don’t drive off the lot wondering if you’ll be back. After all, you trust us with your most precious cargo; we trust you with our reputation.

Give us a call today at Louie and John’s Complete Auto Service. We stand by our work so you won’t be standing by the side of the road.