Are there any benefits to using gas additives.
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You have to remember on most DI engines the injectors gas spray does not contact the exhaust valve or valves so an additive does no good.
Thus the reason Lexus added the extra injector to specifically spray fuel on the exhaust valves.
Thus the reason Lexus added the extra injector to specifically spray fuel on the exhaust valves.
Can you explain what exactly in the "upper cylinder" is being lubricated and how the additve "really cleans things up"? How is that being accomplished in a DI engine?
I don't really see what needs lubricating in a non-DI engine either. The term "upper cylinder lube" is thrown around a lot on here but no one can explain what needs lubing that isn't getting it already.
Originally Posted By: zpinch
Alot of DI engines need an upper cylinder lubricant to keep things clean and lubricated, especially the valves.
Amsoil Pi Performance improver is a guaranteed winner when it comes to combustion chamber cleanliness, really cleans things up and gets your engine running properly. Cleans injectors really well for proper spray pattern. They have a money-back guaranteed MPG gain when using it, 3% IIRC.
I don't really see what needs lubricating in a non-DI engine either. The term "upper cylinder lube" is thrown around a lot on here but no one can explain what needs lubing that isn't getting it already.
Originally Posted By: zpinch
Alot of DI engines need an upper cylinder lubricant to keep things clean and lubricated, especially the valves.
Amsoil Pi Performance improver is a guaranteed winner when it comes to combustion chamber cleanliness, really cleans things up and gets your engine running properly. Cleans injectors really well for proper spray pattern. They have a money-back guaranteed MPG gain when using it, 3% IIRC.
Originally Posted By: -SyN-
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Thus the reason Lexus added the extra injector to specifically spray fuel on the exhaust valves.
I thought they combined port injection with direct injection to get the best of both worlds in terms of performance and emissions. My understanding is that port injection excels in some circumstances like small throttle opening, and from my very limited experience test driving direct injection engines I'd say DI excels in the mid range RPM, with mid to wide throttle opening.
...
Thus the reason Lexus added the extra injector to specifically spray fuel on the exhaust valves.
I thought they combined port injection with direct injection to get the best of both worlds in terms of performance and emissions. My understanding is that port injection excels in some circumstances like small throttle opening, and from my very limited experience test driving direct injection engines I'd say DI excels in the mid range RPM, with mid to wide throttle opening.
Originally Posted By: -SyN-
You have to remember on most DI engines the injectors gas spray does not contact the exhaust valve or valves so an additive does no good.
Thus the reason Lexus added the extra injector to specifically spray fuel on the exhaust valves.
Uh no.
There's no need to spray an exhaust valve down with any kind of detergent. They get plenty hot and anything burns off pretty easily.
They put in additional port injectors, which spray down the intake valves. Spraying down the exhaust valves would probably overload the catalytic converter if the fuel doesn't ignite first.
You have to remember on most DI engines the injectors gas spray does not contact the exhaust valve or valves so an additive does no good.
Thus the reason Lexus added the extra injector to specifically spray fuel on the exhaust valves.
Uh no.
There's no need to spray an exhaust valve down with any kind of detergent. They get plenty hot and anything burns off pretty easily.
They put in additional port injectors, which spray down the intake valves. Spraying down the exhaust valves would probably overload the catalytic converter if the fuel doesn't ignite first.
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Originally Posted By: -SyN-
You have to remember on most DI engines the injectors gas spray does not contact the exhaust valve or valves so an additive does no good.
Thus the reason Lexus added the extra injector to specifically spray fuel on the exhaust valves.
I think you mean intake valves.
You have to remember on most DI engines the injectors gas spray does not contact the exhaust valve or valves so an additive does no good.
Thus the reason Lexus added the extra injector to specifically spray fuel on the exhaust valves.
I think you mean intake valves.
Originally Posted By: -SyN-
Lexus is the only manufacture to care about this issue and actually installed another injector to spray fuel on the exhaust valves.
This is a myth. Toyota specifically stated that the extra injector is for part throttle cylinder filling issues common to DI engines.
It was not added for cleaning, only drivability...
Lexus is the only manufacture to care about this issue and actually installed another injector to spray fuel on the exhaust valves.
This is a myth. Toyota specifically stated that the extra injector is for part throttle cylinder filling issues common to DI engines.
It was not added for cleaning, only drivability...
Well! Maybe I read the article wrong and miss under stood! I do apologize for posting false info.
Originally Posted By: -SyN-
Well! Maybe I read the article wrong and miss under stood! I do apologize for posting false info.
I doubt this is what you call 'false', as they do fit extra injectors. But they were never intended to clean valves.
Perhaps they do. It is a nice benefit if so. But DI engines and their part throttle uneven cylinder filling issues are well known in the automotive industry.
In reality it is a "band aid" solution, not very elegant engineering...
Well! Maybe I read the article wrong and miss under stood! I do apologize for posting false info.
I doubt this is what you call 'false', as they do fit extra injectors. But they were never intended to clean valves.
Perhaps they do. It is a nice benefit if so. But DI engines and their part throttle uneven cylinder filling issues are well known in the automotive industry.
In reality it is a "band aid" solution, not very elegant engineering...
I actually don't recall them saying it was to clean the valves but to keep them wet so the oil vapor from the PCV would not stick and continue build up.
I know my daughters Audi 2.0T has had issues with this DI problem and the dealer had to remove the head and clean the valves by hand. The Carbon Build up was so bad it was throwing miss fire codes.
Service told me there were NO additives to use that would help this issue. Since NO fuel really gets sprayed on too the valves themselves.
This is Just what I was told. I seen the valves before they were cleaned and it was amazing the engine even ran.
Some say a Catch Can might help! Some say a Low SAP oil helps... I don't know! I know we as a family will avoid any DI engines in the future.
I know my daughters Audi 2.0T has had issues with this DI problem and the dealer had to remove the head and clean the valves by hand. The Carbon Build up was so bad it was throwing miss fire codes.
Service told me there were NO additives to use that would help this issue. Since NO fuel really gets sprayed on too the valves themselves.
This is Just what I was told. I seen the valves before they were cleaned and it was amazing the engine even ran.
Some say a Catch Can might help! Some say a Low SAP oil helps... I don't know! I know we as a family will avoid any DI engines in the future.
Thanks Badtlc: for that advice!
I have read that before a few times in the Audi Forums.
I think the key to that is to start doing it early in the engines life..
Because once this stuff gets hard it is like concrete.
Key is I guess don't let it start.
As soon as we get the wifes Edge payed off-->This Audi is gone!
I have read that before a few times in the Audi Forums.
I think the key to that is to start doing it early in the engines life..
Because once this stuff gets hard it is like concrete.
Key is I guess don't let it start.
As soon as we get the wifes Edge payed off-->This Audi is gone!
In Germany why are some DI cars still having problems even running their engines at high rpm's for extended periods of time? Why are they still needing walnut shell blasting? This question has been asked before and got no good answers.
Originally Posted By: demarpaint
In Germany why are some DI cars still having problems even running their engines at high rpm's for extended periods of time? Why are they still needing walnut shell blasting? This question has been asked before and got no good answers.
The silence is deafening.
There likely is no real answer. It should be obvious that this is very platform specific, thus what works for one car may not help at all in a differently designed DI engine.
More testing needed, thank the early adopters!
In Germany why are some DI cars still having problems even running their engines at high rpm's for extended periods of time? Why are they still needing walnut shell blasting? This question has been asked before and got no good answers.
The silence is deafening.
There likely is no real answer. It should be obvious that this is very platform specific, thus what works for one car may not help at all in a differently designed DI engine.
More testing needed, thank the early adopters!
Frank you and i discuss this issue for the last god knows how many years and we are still discussing.
Funny thing is VW/Audi has problems in Germany but SEAT and some Skoda don't seem to be as bad and thats also a VW engine.
When i was at the garage last year i noticed the walnut shell machine didn't have any cobwebs on it.
I guess it has a lot to do with the tune and how its implemented. I don't believe there is any single fix for these issues at this point.
Running the engine for extended periods at XXXX RPM may or may not help some and do nothing for others.
If Mazda for example has a good grip on the problem then they may not need the high RPM runs anyway. IMHO it cant be implemented as a broad brush stroke fix.
IMHO if you don't want problems just avoid DI for now. It will be okay at some point but that point is not today.
Funny thing is VW/Audi has problems in Germany but SEAT and some Skoda don't seem to be as bad and thats also a VW engine.
When i was at the garage last year i noticed the walnut shell machine didn't have any cobwebs on it.
I guess it has a lot to do with the tune and how its implemented. I don't believe there is any single fix for these issues at this point.
Running the engine for extended periods at XXXX RPM may or may not help some and do nothing for others.
If Mazda for example has a good grip on the problem then they may not need the high RPM runs anyway. IMHO it cant be implemented as a broad brush stroke fix.
IMHO if you don't want problems just avoid DI for now. It will be okay at some point but that point is not today.
Thanks fellas for your input!
You all have basically spoken everything I have heard and read before.
I will never own another DI motor. This audi has been one big pain in rear end.
Besides there is NO place around here that I can take the car at that rpm for that amount of time! Besides sitting in the drive way--->That's not happening.
You all have basically spoken everything I have heard and read before.
I will never own another DI motor. This audi has been one big pain in rear end.
Besides there is NO place around here that I can take the car at that rpm for that amount of time! Besides sitting in the drive way--->That's not happening.
Originally Posted By: Trav
Frank you and i discuss this issue for the last god knows how many years and we are still discussing.
Funny thing is VW/Audi has problems in Germany but SEAT and some Skoda don't seem to be as bad and thats also a VW engine.
When i was at the garage last year i noticed the walnut shell machine didn't have any cobwebs on it.
I guess it has a lot to do with the tune and how its implemented. I don't believe there is any single fix for these issues at this point.
Running the engine for extended periods at XXXX RPM may or may not help some and do nothing for others.
If Mazda for example has a good grip on the problem then they may not need the high RPM runs anyway. IMHO it cant be implemented as a broad brush stroke fix.
IMHO if you don't want problems just avoid DI for now. It will be okay at some point but that point is not today.
We do talk about it a lot don't we? We also spoke about the ramifications of running an automatic trans long enough in a lower gear to do the cleanup and stay within legal speed limit. Do you remember that conversation? All I can say is the technology is improving, but it's not there just yet.
Frank you and i discuss this issue for the last god knows how many years and we are still discussing.
Funny thing is VW/Audi has problems in Germany but SEAT and some Skoda don't seem to be as bad and thats also a VW engine.
When i was at the garage last year i noticed the walnut shell machine didn't have any cobwebs on it.
I guess it has a lot to do with the tune and how its implemented. I don't believe there is any single fix for these issues at this point.
Running the engine for extended periods at XXXX RPM may or may not help some and do nothing for others.
If Mazda for example has a good grip on the problem then they may not need the high RPM runs anyway. IMHO it cant be implemented as a broad brush stroke fix.
IMHO if you don't want problems just avoid DI for now. It will be okay at some point but that point is not today.
We do talk about it a lot don't we? We also spoke about the ramifications of running an automatic trans long enough in a lower gear to do the cleanup and stay within legal speed limit. Do you remember that conversation? All I can say is the technology is improving, but it's not there just yet.
Hundreds of hours over the last 6 years. LOL Car people always have a lot to talk about it seems.
I have seen everything come down the road since points/condenser ignition and non emission carbs to the earliest FI systems with pop nozzles and rudimentary engine controls all the way up to todays tech.
Every one of them was a bad idea at the time, most of the tech was trouble prone in some way for a short time.
DI certainly has a future, the injectors are going through a lot of changes right now, better things a coming. IMHO the demand for better fuel economy has driven the manufacturers to release technology before its time, problems were inevitable.
Holding any tranny in a lower gear to gain higher RPM's for an extended period of time is not the best idea. The whole drive train is not going to have the cooling effects as it would going the road at the same RPM in top gear.
and my opinion. And as i have said before, that and $2.25 will get me a med coffee.
I have seen everything come down the road since points/condenser ignition and non emission carbs to the earliest FI systems with pop nozzles and rudimentary engine controls all the way up to todays tech.
Every one of them was a bad idea at the time, most of the tech was trouble prone in some way for a short time.
DI certainly has a future, the injectors are going through a lot of changes right now, better things a coming. IMHO the demand for better fuel economy has driven the manufacturers to release technology before its time, problems were inevitable.
Holding any tranny in a lower gear to gain higher RPM's for an extended period of time is not the best idea. The whole drive train is not going to have the cooling effects as it would going the road at the same RPM in top gear.
Originally Posted By: Trav
DI certainly has a future, the injectors are going through a lot of changes right now, better things a coming. IMHO the demand for better fuel economy has driven the manufacturers to release technology before its time, problems were inevitable.
We agree on all points. FTR DI does have a future, and will probably evolve to be great I'm sure. It's just not there yet. JMO
DI certainly has a future, the injectors are going through a lot of changes right now, better things a coming. IMHO the demand for better fuel economy has driven the manufacturers to release technology before its time, problems were inevitable.
We agree on all points. FTR DI does have a future, and will probably evolve to be great I'm sure. It's just not there yet. JMO
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