Hey everyone, I’m a mechanic but I work on diesel engines, not cars. My wife has a Kia that she takes to the shop for routine service. They keep telling her the car needs a fuel system cleaning. It’s got about 30,000 kilometers on it. Is this something worth doing or just a way for them to make extra money? I’ve never done a fuel system cleaning on any of my own vehicles, and they’ve been fine.
What’s even involved in a fuel system cleaning? Do they take out the injectors? Replace parts like the pump or filters? Flush the system? It sounds expensive, and I’m not sure it’s needed yet. What do you all think?
What engine does it have? GDI engines are known for carbon buildup because the fuel sprays directly into the combustion chamber, skipping the intake valves. If you want to prevent future issues, it might be worth considering.
Usually, a fuel system service has two steps. One cleaner goes into the fuel tank to help clean the injectors, and another is sprayed into the intake to clean deposits in the manifold and on the valves. This can help with buildup caused by the PCV system.
@Franklin
It’s a GDI engine. Thanks for mentioning the carbon buildup issue. But how does a cleaning actually help with that? As a diesel tech, I’d assume you’d need to take the valves out and clean them manually to remove carbon. Am I wrong?
@Darian
Fuel system cleaners do help if they’re done the right way. I’ve been using BG products for years, and they’re pretty effective. Check out this video from BG to see what I mean.
@Franklin
Thanks for sharing the video. I’ll look into what my shop uses. I don’t mind paying for something that works, but I’d hate to spend a lot of money on something that’s just basic fuel additive.
@Darian
Here’s another video that talks about GDI carbon buildup specifically. Check this out. Knowing what’s happening inside your engine can really help you make informed decisions.
@Franklin
Thanks again. I should mention the car has 30,000 kilometers, not miles, so I doubt there’s a lot of buildup yet. Do you think I’d be out of line asking for boroscope pics before they do anything? I provide these for my diesel customers all the time, but I feel like car shops might not be as accommodating.
@Darian
Not at all. Boroscope images would be a great way to confirm if a cleaning is needed. If they’re good at what they do, they should have no issue providing them.
@Darian
I’ve got a GDI engine and use CRC intake valve cleaner. You spray it right at the throttle body, and it’s safe for turbos and intercoolers. Here’s more info if you’re curious: CRC Cleaner Info. GDI engines can definitely benefit from regular cleaning to prevent buildup. Manual cleaning is an option too but can cost $500 or more. The CRC cleaner is only about $12 and works well if you follow the instructions.
@Dakota
Thanks for the info. My shop is asking $200 for their cleaning service. I’m seeing them Saturday, so I’ll ask more about what they actually do.
Darian said: @Dakota
Thanks for the info. My shop is asking $200 for their cleaning service. I’m seeing them Saturday, so I’ll ask more about what they actually do.
If it’s just an additive, it won’t clean the intake valves, but it can help keep the injectors clean. If they do an induction service, it’s more effective since it actually hits the valves.
I’d recommend trying the CRC cleaner first. It’s easy to use and much cheaper. If it helps, you can avoid spending $200 on something unnecessary.
I had it done on my 2012 Sportage SX at 70k. My engine needed a head rebuild at 35k, but I think in your case they might just be trying to sell you extra services. Is the engine running rough or losing power?
For me, there wasn’t much of a difference after the cleaning, but I tend to do more maintenance than necessary just for peace of mind.
You can check Kia’s service schedule online to see if this is even recommended for your mileage. The induction cleaning service works differently from additives—they clean the intake, valves, and more, while additives help with the fuel lines and injectors.