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Posted

my 21 2.7 runs great, no issues, has 34,000 miles

ive read they get carbon build up. is that a big deal on the 2.7?  

should i use injection cleaner in the fuel?

Posted (edited)

i guess it might be depending on the type of driving. my 2.7 has 120k miles, changed the plugs at 70k and it runs as good as new. i have not used any injector cleaner

Edited by silveradosid
  • Like 1
Posted
7 hours ago, silveradosid said:

i guess it might be depending on the type of driving. my 2.7 has 120k miles, changed the plugs at 70k and it runs as good as new. i have not used any injector cleaner

Have you had any issues with your 2.7? I’ve only heard of a few with that kind of mileage so far. 
 

OP, I haven’t read anywhere that carbon buildup is an issue. Just make sure to use top tier fuel. They claim that it’s better than non top tier. I’m not sure about that considering my FIL has delivered fuel for years and said it’s all exactly the same. 

Posted

i have had 3 issues, the pcv fine oil separator failed at 60k, recently i had a turbo problem that was a clamp that attaches the exhaust to the turbo had come loose and turned and was stopping the actuator arm. other than that it likes to eat oil

Posted
On 6/7/2026 at 7:20 AM, Leroy114 said:

my 21 2.7 runs great, no issues, has 34,000 miles

ive read they get carbon build up. is that a big deal on the 2.7?  

should i use injection cleaner in the fuel?

 

All Direct Injection engines risk carbon build up on their intake valves.

 

Adding fuel injection cleaner to the fuel won't help prevent this because the fuel is being sprayed directly into the cylinder.

 

From what I have researched a "walnut shell" cleaning service can successfully remove the built up carbon from the intake valves. However this service is much more expensive than a bottle of Techron.

  • Like 1
Posted
25 minutes ago, VA_Silverado said:

 

All Direct Injection engines risk carbon build up on their intake valves.

 

Adding fuel injection cleaner to the fuel won't help prevent this because the fuel is being sprayed directly into the cylinder.

 

From what I have researched a "walnut shell" cleaning service can successfully remove the built up carbon from the intake valves. However this service is much more expensive than a bottle of Techron.

How often should the Techron be added? im at 34,500 miles and thinking now is the time to start trying to help the carbon buildup.

 

   thanks

Posted
3 hours ago, silveradosid said:

i have had 3 issues, the pcv fine oil separator failed at 60k, recently i had a turbo problem that was a clamp that attaches the exhaust to the turbo had come loose and turned and was stopping the actuator arm. other than that it likes to eat oil

what did the pcv issue cost to remendy? if you don't mind saying

  thanks

Posted (edited)
4 hours ago, Leroy114 said:

How often should the Techron be added? im at 34,500 miles and thinking now is the time to start trying to help the carbon buildup.

 

   thanks

 

 

Techron is a fuel injection cleaner and my point is it won't help prevent carbon build up on your intake valves. I am not aware of any product that can prevent carbon build up on a DI engine.

 

Edited by VA_Silverado
  • Like 1
Posted
11 hours ago, VA_Silverado said:

 

 

Techron is a fuel injection cleaner and my point is it won't help prevent carbon build up on your intake valves. I am not aware of any product that can prevent carbon build up on a DI engine.

 

Thanks for the info, im not going to use it then. ive read our fuel is cleaner than ever today so no need for an additive. at least not often.

 

at 25,000 mile service my dealer wanted to do a fuel system clean, i declined thinking it was  BS. was 150 bucks price

Posted

Most of my vehicles are north of 150K miles. I don’t add anything to the fuel or oil. My gas in town is Kroger gas not a top tier. My wife’s car 2011 Genesis is only driven to town 8 miles then back. I’m not saying additives don’t work. I’ve seen them work miracles on ViceGrip garage. I did partake with the Wynns additive in the CRV through the dealer. I did it only for the warranty. Especially with the CVT transmission. But my daughter needed a car. And of course she’s not following through. I’m only relating my experience. I don’t think they’re needed, generally. 

Posted (edited)

Techron and other "PEA" fuel system cleaners are still useful. They take just about any kind of deposit and dissolve it using the PEA ingredient and then it all gets eliminated in combustion. This can be anything inside the tank, lines, or injectors themselves. You still want to maintain clean injectors and an optimal spray pattern, and direct injection systems need that too. Most good-quality fuel (doesn't have to be Top Tier), as long as you're using your vehicle regularly, should maintain a pretty clean fuel system by design. I don't think it hurts to dump a bottle of Techron or other PEA-based cleaner in every once in a while for a boost. Take note, these cleaners "maintain" clean, they don't undo any severe buildup. It's not a fix in a bottle.

 

It's true, any "fuel system cleaner" you dump in your tank isn't going to be effective at cleaning deposits off of valves. Direct Injects, all of them, unless they are also combination Port Injection like in some Toyotas, will dirty the intake valves over time to some extent.

 

Media-blasting the top end, i.e. "walnut shells" is for severe buildup. Direct Inject top ends can still be chemically flushed and don't require media blasting if the buildup isn't too bad.

 

On a modern direct inject like the 2.7 I'd ask someone who truly knows what they're looking at between 30-50k. Does it need to be cleaned? It can't be just a bottle of cleaner, that won't do it. You'll need a top-end service if there's a lot of buildup.

 

Modern direct injects don't build up like the early ones from 15-20 years ago, but is something to keep an eye on.

 

 

Edited by Atlas
Posted
1 hour ago, Atlas said:

Techron and other "PEA" fuel system cleaners are still useful. They take just about any kind of deposit and dissolve it using the PEA ingredient and then it all gets eliminated in combustion. This can be anything inside the tank, lines, or injectors themselves. You still want to maintain clean injectors and an optimal spray pattern, and direct injection systems need that too. Most good-quality fuel (doesn't have to be Top Tier), as long as you're using your vehicle regularly, should maintain a pretty clean fuel system by design. I don't think it hurts to dump a bottle of Techron or other PEA-based cleaner in every once in a while for a boost. Take note, these cleaners "maintain" clean, they don't undo any severe buildup. It's not a fix in a bottle.

 

It's true, any "fuel system cleaner" you dump in your tank isn't going to be effective at cleaning deposits off of valves. Direct Injects, all of them, unless they are also combination Port Injection like in some Toyotas, will dirty the intake valves over time to some extent.

 

Media-blasting the top end, i.e. "walnut shells" is for severe buildup. Direct Inject top ends can still be chemically flushed and don't require media blasting if the buildup isn't too bad.

 

On a modern direct inject like the 2.7 I'd ask someone who truly knows what they're looking at between 30-50k. Does it need to be cleaned? It can't be just a bottle of cleaner, that won't do it. You'll need a top-end service if there's a lot of buildup.

 

Modern direct injects don't build up like the early ones from 15-20 years ago, but is something to keep an eye on.

 

 

You heard of chevron fuel? They have the additive. I trust other brands do to. I let my Hyundai service writer talk me into injecting cleaner on my wife’s Genesis. It was running fine no issues. After nothing was changed. How could it? It was fine before hand. I guess if it makes people feel better. I agree about buying fuel where the most traffic is.

Posted
4 hours ago, KARNUT said:

You heard of chevron fuel? They have the additive. I trust other brands do to. I let my Hyundai service writer talk me into injecting cleaner on my wife’s Genesis. It was running fine no issues. After nothing was changed. How could it? It was fine before hand. I guess if it makes people feel better. I agree about buying fuel where the most traffic is.

 

Never heard of the stuff. Glad it made you feel better though. I wouldn't suggest drinking it.

Posted
8 minutes ago, Atlas said:

 

Never heard of the stuff. Glad it made you feel better though. I wouldn't suggest drinking it.

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