Hey there, readers–
Today’s blog is all about something you’ve probably seen in the auto shop, but maybe something a lot of you have never used before. I’m talking about fuel injector cleaners. I’ve actually gotten a few questions on here about them, and I know a lot of folks I talk cars with want to know my thoughts, so I figured it deserved a whole blog post. I’m a big fan of these little solutions, so let me tell you why, and what you can expect from them.
Essentially, fuel injector cleaners are exactly what they say they are, cleaners for your fuel injectors. If you know anything about injection motors, they use the injector nozzles to get a fine spray of fuel into the combustion chamber, which fires and gives the engine power. The idea is, the more fuel you burn, the more soot and sludge ends up on the injectors. It’s a tiny effect at first, but over time, the built up dirt can make the injector spray funny, and rob the engine of some of its power.
In an old car, that’s usually why you can fix every part in the drivetrain and not see all those horses come back to the stable. You can also tell your injectors are clogged up if you have a sluggish start or a lot of noise from the engine. Smoggy exhaust is a warning sign too. Anyway, there are a lot of different things a dirty injector set affects, but the main thing is that you lose power.
The cleaner is a fluid solution you get in a little bottle, which you run through the fuel line. It’s basically a detergent. If you think of it like doing laundry, your motor is your clothes, your tank of fuel is the water the machine runs through, and the soap is the small amount that’s run through to do the cleaning. It’s the same general idea.
In a lot of new cars, you might not need to worry about your injectors. We’ve known about dirty injector issues for years now, and so good fuel today has detergents (cleaners) already added to make it burn smoother, and we’ve added lubricants to compensate for the fact that we don’t use lead anymore. New cars are also designed better to keep the injectors firing without any trouble, where before most people weren’t even thinking about what fuel itself would do to a car’s innards.
But in an older car or if you don’t have a really good filling station that gives you high-quality fuel, you’re still going to end up with some accumulation over time. That’s why I use these things every so often, and especially when I get a car in the shop for the first time. They’re simply a great all-around improver for anything power-related, and in my opinion, they’re a cheap way to see if you can make a motor run better without taking it completely apart. It never hurts to try one, and I’d say it almost always helps.
If you want my advice, you’ll use one on any car more than 10 years old as a routine part of your maintenance. And unless you’re really confident in the quality of the gas you’re running through the vehicle, you should use one when you change your oil in a new car, too.
The one type of motor to never skip injector cleanings on is a diesel. They’re really important for diesels, because diesel is such a dirty, messy fuel. I don’t drive any diesels myself, but I’ve worked on them plenty, and I can tell you from experience that nothing gets fouled up as easily or as quickly as a diesel engine. You’re going to want to add some cleaner or an additive with every tank. I would suggest Liqui-Moly, or Stanadyne, but you can find a longer list over at fuelinjectorcleaner.xyz .
So, to wrap up, my take is that no, these cleaners aren’t snake oil, but they’re not super necessary if you drive a brand new car, use really good fuel, and take care of it otherwise. Think about what I just said, though. Those are ideal circumstances, and you almost certainly aren’t living in an ideal world!
Here’s one thing to think about: new fuel is hardly clean. There’s a law on the books that all fuel in this country has to have 10% ethanol in it. That’s corn fuel, if you’re not familiar with it, and all you really need to know about it is it burns like diesel. That’s to say it’s messy, dirty, and it leaves a lot of itself behind. It doesn’t really matter how much detergent they put in the fuel if they’re also putting all that crud in. So even under ideal circumstances, you’re never going to get close to a clean burn. A lot of people forget about ethanol when they talk about how newer cars using nice fuels don’t need injector cleaners. It’s actually something that can be worse in some cases for new cars, especially the European and Japanese ones, because they’re fine-tuned for countries which don’t use ethanol (i.e. everybody else).
So, getting back to the point I don’t use the cleaners religiously in the newer cars I drive, but you can sure bet I use them in the older vehicles and about once an oil change in the new cars. I hope this helps you out, let me know if you want any more specific thoughts. I would also recommend reading this cleaning guide for a fuel engine and having a look at http://fuelinjectorcleaner.xyz/diesel if you drive diesel.