David Reviews the Best Fuel System Cleaners

s someone who uses older cars most of the year, and is passionate about restoring them to their full glory, I have a secret to introduce you to: the magic of fuel systems cleaners.

Now, there can be any number of problems with an older car. The frames are probably rusting, so you’ll have to grind them down and then coat them to keep it from getting worse. You’ll almost certainly have to switch out the upholstery and mats, and I generally re-panel at least one interior every year because it’s in such rough shape. But for all the fixes you make, the biggest problem is usually the engine.

It’s just a fact of mechanical life that engines don’t age well. They lose power over time, and while you can focus on tweaking individual components and make small fixes, it’s often a subjective problem that’s hard to pin down. The whole engine is weaker than it should be for no apparent reason.

Well, there is one major reason that you won’t find in any diagram. It’s the fact that combustion engines that power our vehicles are dirty, dirty machines. They don’t burn as cleanly as we’d like them to, especially not on older cars. Older cars burn very dirty indeed, that’s why you’re not allowed to drive them without adding a catalytic converter these days. And if you can see all that smog going out into the air, it only stands to reason that the insides of the motor are gonna be dirty as well, right?

The fact is, all that gunk, soot, and accumulated filth is the main culprit in taking your engine’s horse pen and opening the gates. It slowly erodes your power so that no matter what you do, you can’t get your motor going at full steam. It’s not one component–your whole system is clogged, and you’re gonna have to give it a thorough cleaning.

That’s what fuel systems cleaners are designed to do. They basically scour every last inch from the fuel lines to the exhaust output, and get rid of all the soot and grime. It’s my solution for how to care for your car’s engine all at once–just use an all-in-one cleaner like these. Injector cleaners get it all, and since they’re washing around in the gas, they can do a better job cleaning into tricky spots than you can, trust me.

Now, generally, fuel system cleaners are made to be run through the fuel line. So you don’t have to do anything really mechanical, you just pour it in the gas cap and keep on driving. But I find that with a really old engine, you’re best advised to get a kit that you apply directly to the metal surfaces inside the engine when the car’s in the shop. 3M makes the best one I’ve found. It comes with some cleaner that you can spray with a wand into the combustion chamber to get all the internal parts directly.

So, if your old motor is lacking in power for no obvious reason, I’d say you should go out and get a fuel system cleaner. My advice is to get a kit for the best initial results, do the whole fuel line carefully, then use a down the hatch cleaner every couple months to keep things going smoothly.

My preference for an in the tank cleaner is something called BG44K. That’s the least technical name you’re gonna find for it, so just plug that into google. I like it because it’s the most concentrated one I’ve found to date, and that means you don’t have to use it nearly as often as the weaker varieties. It’s basically a professional grade solution, and most good mechanics keep a couple cans around for really tough messes. You don’t have to go for that one, though, since there are lots of different ones that each do something a bit differently. Read this article for a good overview of all the different kinds you can get.

Basically, you have to choose between something that you add to each tank, and something more concentrated that you’ll only feed in once every 6 months or so. Once you find one you like, make sure to buy it in bulk to save money. But then you’re good to go! Your motor will thank me.