BBB
Active Member
So I have my second service tomorrow and the service department is wanting to add injector fluid as part of the service. I've never used this stuff in the past. I see this as an up-sell. Any need for this stuff?

Kia has released TSB recommending adding 12 oz Techron Concentrate Plus fuel system cleaner at every 7500 mile oil change interval if Top Tier fuel is not available.
The biggest problem with DI engines is not injector nozzle clogging, it's valve stem deposits.Anything that is put into your fuel tank and claims to reduce or clean carbon build up is snake oil, DI motors to not see fuel spray on the valves. The only thing a fuel treatment will clean is the actual injector nozzles.
As for Kia's recommendation, as echoed above, if you're not using top tier fuel with added detergents, I would use this since it is dictated in the owners manual and Kia could revoke warranty if they claim (or can prove) a lack of additives or their supplement (not used) causes issues with the engine.
The valves in theory never see a spray of fuel in direct injection. I saw a theory once that a spray of fuel (probably dependent on the injector location) that happens when the intake valve is open, with all the swirly vortex of air could theoretically cause spray to hit the valve while open, but I think that's a pipe dream.How does it affect the valve stems, since it's injected directly into the combustion chamber? It therefore bypasses the valve stems, whereas port injection directs the fuel along the stems on their way into the combustion chamber.
If you are using top tier gasoline you shouldn't need injector service. As far as intake valves go, the only way to properly clean them is to remove intake manifold and clean them manually. Cleaned mine at 40k miles when changing plugs and there were quite a lot of buildup on them.I'm bumping this back from the dead-scheduled to have the injectors cleaned at next service. Anyone know if they actually clean them or just pour in a bottle of Techron?
I did the Sea Foam at about 10k. I'm thinking you meant something else?If you are using top tier gasoline you shouldn't need injector service. As far as intake valves go, the only way to properly clean them is to remove intake manifold and clean them manually. Cleaned mine at 40k miles when changing plugs and there were quite a lot of buildup on them.
No matter what you put into gas tank, it is not gonna clean the valves. Some people spray sea foam into air intake. I don't belive it is doing anything either. After i removed the manifold and let the valves soak for 2 hours, i still had to scrape all the crap off the valves. So i just dont see, how spraying, whatever cleaner you are using, while the engine is working and sucking all the cleaner right into combustion chamber, is doing anything, but burning it inside the cylinders.I did the Sea Foam at about 10k. I'm thinking you meant something else?
Remove upper and lower sections of intake manifold. Let the valves (closed ports) soak in the cleaner for 2 hours, and than use old tooth brush and metal picks to scrape the valves. Rotate the engine, to close the open ports,and repeat the process.What was your cleaning process?