[pnoman]

I just bought a new Soul Base 1.6 with automatic and love it so far (1 week and 200 miles). Very comfortable and versatile, and so far getting about 29MPG on the trip computer in mixed stop-and-go and hilly 2-lane roads while trying to vary engine speed for proper break in.

One question I have, though, is about possible carbon buildup on the intake valves. Since DI injects the fuel directly into the cylinder, regular fuel cleaners do not pass over the outside face of the intake valves, meaning they don't get the cleaning effect. Now the only thing passing by the intake valves is fresh air and the oil fumes from the PCV. From what I've read at many sources, the oil fumes can cause deposits to build up over time. This requires an engine disassembly in the worst-case scenarios in higher mileage vehicles.

However, I was wondering if Kia engineers had taken proper steps to ensure oil droplets do not re-enter the intake tract. I have seen aftermarket "catch cans" with internal screens and baffling to catch oil particles but am afraid of voiding the warranty. So, my thought is to switch to synthetic oil after the break-in period (probably between 5K and 10 miles). Synthetics should have fewer (if any) hydrocarbon emissions caused by heat, so I'm thinking less fumes = less deposits in the intake tract.

** THIS IS NOT MEANT TO BE ANOTHER 'WHAT BRAND OF OIL IS BEST' RANT ** Simply, I would like thoughts on whether 1) there is a history of intake deposits problems with the Kia 1.6 DI and 2) if using pure synthetic (100% synthetic - not blended or using petroleum base) would reduce the PCV emissions.

Thanks!

 

[The Old Grouch]

First, Kia recommends the use of "top tier" gasoline to minimize carbon buildup, particularly in the 1.6 mill. Just google (or bing, or chrome) "top tier gas" to find out who sells it it your area. Don't know about the catch cans, but switching to synthetic will be a plus all the way around for your engine at the very least.

 

[SoulCollector]

Use top tier fuel only. Look them up online, there is a list. ( Shell, Chevron, Exxon etc.. ). And every oil change, put in a bottle of Chevron Techron fuel system cleaner. You don't have too if using Top Tier fuel but it doesn't hurt it as Kia clearly states thats what they use and they approve it. Do that and you will never have a problem.

 

[pnoman]

Thanks for the replies. I understand about using Top Tier gas and additives to keep the injectors clean. My concern is the outer face (away from the cylinder) and stem of the intake valves, which are "upstream" and therefore do not benefit from the fuel or additives.

 

[SoulCollector]

I never heard of anyone complaining about anything besides carbon from bad fuel. Kia for 2014 just converted the 2.0 to GDI to match the 1.6L thats been that way for a few years now. I don't think they would be doing that if GDI was junk.

 

[TechnoMage]

Use top tier fuel only. Look them up online, there is a list. ( Shell, Chevron, Exxon etc.. ). And every oil change, put in a bottle of Chevron Techron fuel system cleaner. You don't have too if using Top Tier fuel but it doesn't hurt it as Kia clearly states that's what they use and they approve it. Do that and you will never have a problem.

The Kia Soul engine certainly Ain't yo daddy's Chevrolet. :laughonfloor

Our little engines are just about the most High Tech engines ever put in family cars.
For instance, they are: DOHC, DFI, VVT, with "Igniters" for every spark plug, which in themselves are very High Tech.

I sometimes feel like I'm driving a car that was reverse engineered from an Alien Space Ship. :big grin:

As I understand the Fuel Injector problem, it's carbon buildup around the injector itself, not on the valves.
The Top Tier gasolines are supposed to have additives (detergents) that will either prevent this carbon buildup or clean it away. But how many of us can absolutely guarantee that we will only use Top Tier gas.
I try, but I can't guarantee it. So, I just do what Kia recommends and put in a small bottle of "Techron" additive, in my gas tank, with every oil change. (3k)
The smallest bottle, and also the cheapest, is the one that will treat up to 15 gallons of gas.

Buy Chevron Techron Concentrate Fuel System Cleaner (12 oz.) 67740 at Advance Auto Parts

It's a small thing to do, to keep our great little cars running at peak performance. Eh?

TM

 

[mountain_soul]

As I understand the Fuel Injector problem, it's carbon buildup around the injector itself, not on the valves.

I agree with the OP, the primary issue with direct injection is definitely build up on the intake valves. Since DI injects fuel into the cylinder itself, the intake valves aren't being "cleaned" by the fuel mixture. In early DI designs, this could lead to build up that eventually caused reduced performance and possibly even valve/engine damage if taken to an extreme.

Regarding the OP's question:

Most of these problems seem to affect early DI designs - designs that adapted existing engines to DI. We've come along way since then and most DI engines now were designed from the beginning with DI in mind. So, the early DI problems are mostly a thing of the past, but something to keep in mind. From articles I've read, the problematic cars seem to have a dirtier EGR system that wasn't an issue without DI, but becomes a problem when DI is implemented.

The Kia 1.6 GDI design is still relatively new since it was first introduced for the 2012 MY. It's probably still too new to know for certain how it will fare in real world conditions over the long haul. But, with every manufacturer shifting to DI tech and Kia's long warranty, I can't imagine that it wasn't engineered to handle a long life without valve issues. Kia's shift to GDI for the 2.0 also speaks to their faith in their DI design. Additionally, both the 1.6 and 2.0 GDI benefit from what was learned about DI problems in the early years of DI (ask those VW/Audi and Lexus owners).

I would second the move to synthetic oil just because it's good for the engine and probably (IMHO) gives you a little more hedge against any possible future build up issues.

Edit: Link to article about DI problems.

Direct Injection Fouls Some Early Adopters

 

[pnoman]

Thanks for including that link. That is one of the articles I read, but had trouble finding it again (lack of time didn't help) to add to the thread. Good reading. Looks like VW/Audi owners got hit hard, but maybe Kia has had time to learn from their mistakes.

I agree with the OP, the primary issue with direct injection is definitely build up on the intake valves. Since DI injects fuel into the cylinder itself, the intake valves aren't being "cleaned" by the fuel mixture. In early DI designs, this could lead to build up that eventually caused reduced performance and possibly even valve/engine damage if taken to an extreme.

Regarding the OP's question:

Most of these problems seem to affect early DI designs - designs that adapted existing engines to DI. We've come along way since then and most DI engines now were designed from the beginning with DI in mind. So, the early DI problems are mostly a thing of the past, but something to keep in mind. From articles I've read, the problematic cars seem to have a dirtier EGR system that wasn't an issue without DI, but becomes a problem when DI is implemented.

The Kia 1.6 GDI design is still relatively new since it was first introduced for the 2012 MY. It's probably still too new to know for certain how it will fare in real world conditions over the long haul. But, with every manufacturer shifting to DI tech and Kia's long warranty, I can't imagine that it wasn't engineered to handle a long life without valve issues. Kia's shift to GDI for the 2.0 also speaks to their faith in their DI design. Additionally, both the 1.6 and 2.0 GDI benefit from what was learned about DI problems in the early years of DI (ask those VW/Audi and Lexus owners).

I would second the move to synthetic oil just because it's good for the engine and probably (IMHO) gives you a little more hedge against any possible future build up issues.

Edit: Link to article about DI problems.

Direct Injection Fouls Some Early Adopters

 

[Lakeman]

In stead of finding and paying for top tear gas wouldn't it be easier to just add the Techron every 3000 or so miles? I buy a lot of my gas at Wal Mart (Murphy oil).

 

[dmwagner]

Thanks for the replies. I understand about using Top Tier gas and additives to keep the injectors clean. My concern is the outer face (away from the cylinder) and stem of the intake valves, which are "upstream" and therefore do not benefit from the fuel or additives.

The valves rotate once the engine hits a certain RPM. I don't know what that RPM is in this engine, but just don't drive your car like granny and you will be ok.

http://www.metacafe.com/watch/1755605/valve_guide_and_valve_rotation/

 

[SoulCollector]

The valves rotate once the engine hits a certain RPM. I don't know what that RPM is in this engine, but just don't drive your car like granny and you will be ok.

Valve Guide and Valve Rotation - Video

HOLD ON MISS DAISY!! (redlines it!)

 

[SoulCollector]

In stead of finding and paying for top tear gas wouldn't it be easier to just add the Techron every 3000 or so miles? I buy a lot of my gas at Wal Mart (Murphy oil).

You can but you best hope that Techron cleans it all. I'm not risking it myself. The Top Tier gas doesn't cost that much more if any.

 

[pnoman]

Just a repost of mountain_soul's link that explains the problem better than I did, and also explains why gasoline and additives don't really matter much in regards to the intake valves in the case of DI. Please read. Thanks.

Direct Injection Fouls Some Early Adopters - AutoObserver

 

[TechnoMage]

I too buy Wal-Mart (Murphy) gas, and Race Track Gas, and Pure Gas and whatever is the cheapest on the strip at the time I need fuel. Except for some additives, it's all Barge Gas anyway.

That's not to say that I never buy Top Tier Gas, because I do, but just not always. I have CC's for all the Top Tier stations close to my home.

But just for safety, and since Kia recommends it, I do use Techron fuel system additive. (at least once, per oil change)
It's a small thing to do for my precious little Gertrude.
She takes good care of me and I do my best to take good care of her.

I also use the Worlds Most Expensive oil additive, which helps my little 1.6 run smoother, cooler and longer with a higher level of performance. But that's food for another thread.

Cheers Mates!
TechnoMage

 

[The Old Grouch]

I too buy Wal-Mart (Murphy) gas, and Race Track Gas, and Pure Gas and whatever is the cheapest on the strip at the time I need fuel. Except for some additives, it's all Barge Gas anyway.

That's not to say that I never buy Top Tier Gas, because I do, but just not always. I have CC's for all the Top Tier stations close to my home.

But just for safety, and since Kia recommends it, I do use Techron fuel system additive. (at least once, per oil change)
It's a small thing to do for my precious little Gertrude.
She takes good care of me and I do my best to take good care of her.

I also use the Worlds Most Expensive oil additive, which helps my little 1.6 run smoother, cooler and longer with a higher level of performance. But that's food for another thread.

Cheers Mates!
TechnoMage

It may all be "barge gas", but the difference is in the additives that are added to the gas as it's being loaded into the tanker trucks for delivery to the stations. Each brand has it's own ratios and types of additives, so just because the trucks all load form the same fuel terminal in a given area doesn't mean that it's all the same fuel. I had one fuel hauler explain to me one time how he would put a bit more of the cleaner additives in the fuel that was going to stations where he would be treated better while delivering than he did where he was treated like dirt.

 

[AlienGreenSoul]

I've been doing some reading on GDI engines in general and it appears they have a problem with carbon build up on the intake valves resulting in poor operation upon startup from the design my worry (I just got a 2013 1.6L soul 38000 miles) does this engine also have those same issues? i do use exxon top tier fuel and use lucas fuel treatment does this cars engine have those same characteristics as the ones having trouble with the carbon build up or is the design differant thanks

 

[FLHamster]

The only fuel additive that's suggested by Kia or Kia dealers, is "Techron" from Chevron.

I'm a bit confused, why there would be any carbon buildup on the intake valves anyway. The only carbon buildup that affects the CDI engine is on the Fuel Injectors themselves.
Since I buy the cheapest fuel I can for whatever area I'm in at the time, I just add a bottle of Techron fuel system cleaner ever 3k miles, along with the rest of my 3k Maintenance. Now at 60K+ miles, I've never had the first hint of any carbon buildup in my engine at all. I've never had any misfires, poor starting or any other engine failures, in five years.

I don't baby my engine either. Some would say that I drive it like I stole it. Well, not that bad, but I do red-line it as often as is convenient.

Good Luck, and Happy Motoring!
FL Hamster

 

[SoNic67]

Since DI injects the fuel directly into the cylinder, regular fuel cleaners do not pass over the outside face of the intake valves, meaning they don't get the cleaning effect. Now the only thing passing by the intake valves is fresh air and the oil fumes from the PCV. From what I've read at many sources, the oil fumes can cause deposits to build up over time. This requires an engine disassembly in the worst-case scenarios in higher mileage vehicles.

Spot-on. Sure there is a lot of blow-by on those new economical engines (less tight cylinder rings, less friction), and the more you can do to help them, the longer they will last. I avoided buying a GDI car for now (or Turbo), and I intend to keep avoiding them.
However, I am using synthetic oil in all my cars anyway, there is no reason why I should "save" money on something that I do maximum twice a year (I do my own oil changes, so I save there).
I am adding Techron now and then, because is recommended by Hyundai/Kia and Mercedes. That's good enough to me.

To clean the intake valves you could use the Seafoam that gets injected right past the throttle valve, but I am not sure how that works with the GDI engines (more sensitive to the air/fuel ratio?)

I'm a bit confused, why there would be any carbon buildup on the intake valves anyway. The only carbon buildup that affects the CDI engine is on the Fuel Injectors themselves. :

The first post is pretty clear, you just need to read it .
The GDI system injects fuel directly inside the cylinder, around the spark plug location. The fuel it doesn't "wash" the intake valve anymore, like is the case when the injection happens "outside" of cylinder, close to the intake valve.
The exhaust valves are hotter than the intake valves, because of the hot exhaust gases passing by. Any carbon build-up gets burned on the exhaust valves.
The intake valves not being "washed" by gasoline (detergents) have less chances to be cleaned up so build-up of carbon remains on the intake.

 

[The Sradiator]

It's time to take your Korean car for an "Italian tune up"...

 

[The Sradiator]

On a serious note (I hate when this happens) it's going to take more than a can of any aerosol product to clean dislodge coked on deposits on the back of your valves.
The best way to remove deposits is to prevent them from the start.
The catch can controversy continues to be a viable option in valve-train health.
With the 100k warranty though the issue may only be an issue for those who keep their souls till death do them part and not for those who lease or drive under the 12k a year average.