DI intake valves CAN be cleaned with PEA?

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According to this article "A vehicle that had run for 20,100 km in Example 4 was reassembled with deposits intact. The vehicle run for an additional 1,100 km using the same fuel described in Example 4 but with the addition of the polyetheramine (PEA) from Example 5 at an order of magnitude increased treatment level; that is, an aftermarket treatment level. The concentration of PEA in the treated fuel was 21 ppm by weight of nitrogen and was 3200 ppm by weight on an actives basis. It was also found that intake valve deposits, which are not directly impacted by additive in DISE engines under normal dosages/operating modes, were reduced by 23% by this treatment." Found it here: http://www.google.com/patents/WO2003078553A2?cl=en They mention that usually in DI engines valve deposits are not affected by fuel additives but in their test they showed that at higher concentrations it can reduce the deposits. I wonder what concentration of something like Redline SI-1 that translates to?
 
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There are some diesel engines here with DI that are in generator service with instructions to use a PEA additive in the fuel. They function as back up power and generally run about 20 hours a month. A service bulletin a few years ago advised doubling the original dose because of valve deposits.
 
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Maybe why Hyundai recommends Thechron (in Hyundai packaging) every service visit or 5k miles and top tier fuel.
 
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Interesting results. I don't have time to read the full article right now, but I'll check it out later.
 
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Originally Posted By: wemay
Maybe why Hyundai recommends Thechron (in Hyundai packaging) every service visit or 5k miles and top tier fuel.
Hyundia/Kia is pushing Techron for all of their cars, not just ones with DI.
 
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I have been overdoing it by using Gumout AIO in one tank (12 gallons) when it is recommended for up to 35 gallons. I'm thinking that might not be so bad of an idea now. I got a bit worried when the Gumout Q&A said 18gal minimum for the AIO product.
 
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Originally Posted By: demarpaint
How does the product get to the back of the intake valves to clean them?
Valve timing. IIRC ford does this. Others like audi Did not at least on first gen DI and they had massive issues with it.
 
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Originally Posted By: Rand
Originally Posted By: demarpaint
How does the product get to the back of the intake valves to clean them?
Valve timing. IIRC ford does this. Others like audi Did not at least on first gen DI and they had massive issues with it.
Thanks. So if you have an early generation DI engine it isn't going to work?
 

crw

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Originally Posted By: Rand
Originally Posted By: demarpaint
How does the product get to the back of the intake valves to clean them?
Valve timing. IIRC ford does this. Others like audi Did not at least on first gen DI and they had massive issues with it.
Huh? OK, are we saying that the fuel and cleaner mixture gets pushed out of the cylinder into the valve chamber in sufficient quantity to clean the valves?
 
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A question to resident GDI experts; since the fuel is injected on the intake stroke, why does the fuel needs to be at 2000 psi? Isn't there is a negative pressure (aka vacuum) in the cylinder during the intake stroke? Another question:- CRC generally don't make snake oil type products but is it really possible to melt the carbon deposit on the back of the valve by spraying a strong solution? Why doesn't they conduct an experiment to show cleaning off the carbon-ed up valve on camera?
 
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I run a 20 oz. bottle of Techron through my Mazda every 3k miles and only use Top Tier fuel. So far it appears to have kept me from needing to clean/replace the EGR valve for a second time...
 
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Originally Posted By: crw
Originally Posted By: Rand
Originally Posted By: demarpaint
How does the product get to the back of the intake valves to clean them?
Valve timing. IIRC ford does this. Others like audi Did not at least on first gen DI and they had massive issues with it.
Huh? OK, are we saying that the fuel and cleaner mixture gets pushed out of the cylinder into the valve chamber in sufficient quantity to clean the valves?
That's why I asked. From what I've gathered here and from talking with experts there aren't any in tank cleaners that will work, unless something has changed with the rolling out of the 2015's that I'm not aware of.
 

crw

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It's amazing how many people still don't understand the issue of direct injection vs. legacy fuel injection and the cleaning of valves.
 
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Originally Posted By: Vikas
A question to resident GDI experts; since the fuel is injected on the intake stroke, why does the fuel needs to be at 2000 psi? Isn't there is a negative pressure (aka vacuum) in the cylinder during the intake stroke? Another question:- CRC generally don't make snake oil type products but is it really possible to melt the carbon deposit on the back of the valve by spraying a strong solution? Why doesn't they conduct an experiment to show cleaning off the carbon-ed up valve on camera?
DI engines typically have a stratified burn mode (ultra lean) where the ignition can occur during compression stroke. Not too mention the injector has to be able to withstand the pressures of combustion so that air/fuel doesn't get pushed into the injector opening and sent up stream into the fuel line.
 
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Originally Posted By: Vikas
A question to resident GDI experts; since the fuel is injected on the intake stroke, why does the fuel needs to be at 2000 psi? Isn't there is a negative pressure (aka vacuum) in the cylinder during the intake stroke?
The primary advantage of injecting fuel at several hundred bar in DI systems is the cooling effect of the injected fuel due to the 'latent heat of vaporization'. Similarly to refrigerant gas going from high pressure liquid to low pressure vapour across the TXvalve/orifice, so too does the high pressure fuel act as a "refrigerant" going from high pressure fuel rail to low pressure combustion chamber. This is typically why GDI engines have higher static compression ratios (and meatier torque curves) compared to a port injected equivalent; because the cooling of the DI fuel injection is being exploited for better efficiency. Now the only way for fuel additives to affect the valve deposits, is for the engine to be operated in 'atkinson' mode, where injection occurs during the intake stroke and intake port reversion is intended.
 
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Originally Posted By: jrustles
Now the only way for fuel additives to affect the valve deposits, is for the engine to be operated in 'atkinson' mode, where injection occurs during the intake stroke and intake port reversion is intended.
Mazda does this on the new SkyActiv engines in addition to keeping the intake valves hotter to prevent deposits from forming. This also operates in conjunction with the 'passive egr' functions some vehicles have. Also for those with deposits, driving it a gear lower on the highway can sometimes bake off some of the grossness much like the self-clean of your oven. The Italian tune-up is back!
 
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Originally Posted By: jrustles
... Now the only way for fuel additives to affect the valve deposits, is for the engine to be operated in 'atkinson' mode, where injection occurs during the intake stroke and intake port reversion is intended.
Just a Q to show my ignorance: If intake port reversion is done with injected fuel in that air, as would be necessary to get some PEA on the outside of the intake valve, wouldn't this also put some atomized fuel out of the cylinder into the intake runner, with potential pollution and hazards?
 
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Yes some air and fuel ventures out into the intake port and quite possibly as far out as the manifold runner when the valve timing is set very retarded. What hazard does this pose? Backfiring would require an ignition source in the intake port. Pollution, presumably means to the environment- well the throttle body, or more accurately the air filter inlet, is a long, long ways away from the intake port.
 
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