Has anyone scraped off deposit samples and sent it for testing? That might reveal what in the oil is breaking down and getting left behind via PCV. And help owners avoid oils that are higher in certain additives.
Regarding intake valve desposits with DI..
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It's the VIIs.
It would be interesting to see if there is manganese in the deposits, indicating that gas does indeed recirculate back into the intake tract.
It would be interesting to see if there is manganese in the deposits, indicating that gas does indeed recirculate back into the intake tract.
What's the typical composition of VII's?
I'm ignorant in this are of DI so please excuse me if I make it to well known... I just wanted to touch on a few things about valve deposits I have questions about.. The valves will still be affected by the combustion process, but does not get the gasoline solvent wash... that thought crossed my mind in a kind of domino effect, once the process starts it seems with a build up on the valves it would start to build faster, and faster because the contaminates have something to hold to.
I'm sure there is some amount of gasoline getting onto the valves, apparently not enough to do any good though. I really can't see how any oil will reduce the valve deposits, unless your getting a lot of blow by.. which in this case I have seen many engines that had blowby, and they were spotless in the combustion chamber area.. it would blow your mind the internals around the head, valve etc would be spotless.. compared to an engine that used no oil, what everyone would call a great engine would be carbonized up as normal in the combustion area.
I'm not sure where DI is going, but this is going to be a hold back for DI until they get it worked out whatever that way may be. I will say that I'm all for DI, but I wouldn't purchase one now because of this... but DI is a far better engineering means of delivering fuel than what we have been using. Less parts, more control of the combustion process, and the option to extend the power stroke out much further driving the economy up.
I wonder if the can raise combustion temperatures high enough to prevent the deposits from forming by requiring a higher compression. As far as I know it's impossible ( I know anything is possible) to use a "non stick" material for the valves, this residue could stick to a greased monkey combined with the combustion pressure, heat etc it seems you couldn't ask for better conditions.
Other things to look at, combustion shape, placement of injectors, and maybe to some extent valve material... and I'm just a ignorant person, I'm sure the car manufacture engineers have much better ideas, and know what they are talking about..
I'm sure there is some amount of gasoline getting onto the valves, apparently not enough to do any good though. I really can't see how any oil will reduce the valve deposits, unless your getting a lot of blow by.. which in this case I have seen many engines that had blowby, and they were spotless in the combustion chamber area.. it would blow your mind the internals around the head, valve etc would be spotless.. compared to an engine that used no oil, what everyone would call a great engine would be carbonized up as normal in the combustion area.
I'm not sure where DI is going, but this is going to be a hold back for DI until they get it worked out whatever that way may be. I will say that I'm all for DI, but I wouldn't purchase one now because of this... but DI is a far better engineering means of delivering fuel than what we have been using. Less parts, more control of the combustion process, and the option to extend the power stroke out much further driving the economy up.
I wonder if the can raise combustion temperatures high enough to prevent the deposits from forming by requiring a higher compression. As far as I know it's impossible ( I know anything is possible) to use a "non stick" material for the valves, this residue could stick to a greased monkey combined with the combustion pressure, heat etc it seems you couldn't ask for better conditions.
Other things to look at, combustion shape, placement of injectors, and maybe to some extent valve material... and I'm just a ignorant person, I'm sure the car manufacture engineers have much better ideas, and know what they are talking about..
I wonder if this will end up like modern diesels and the need to add urea solutions for the catalyst. Only here, there would be a tank to add something that would vaporize down the intake to clean the valves. If and when this is shown to affect pollution and catalyst life as the valves begin to work improperly, there will be mandated changes.
JHZR2
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Im not sure there is a specific test that would work for that. One would need a few hundred mg if sample ground really fine and then put into a pellet. Not sure if the carbon (which is what the main constituent is regardless of if it is VII or something else) could be discerned as one form or another.
Originally Posted By: Boomer
I wonder if this will end up like modern diesels and the need to add urea solutions for the catalyst. Only here, there would be a tank to add something that would vaporize down the intake to clean the valves. If and when this is shown to affect pollution and catalyst life as the valves begin to work improperly, there will be mandated changes.
ULSD is mandatory and I've read where some believe that they expect intake deposits to be lessened due to the lower sulphur levels and the use of low/mid-SAPS oils.
If do a search on TDI, intake, build up you'll see photos of highly carbonized intakes and comments from VW mechanics who say they're getting fewer and fewer intakes to clean with the USLD switch.
Lucky for us oil burners we're ahead of the curve being that our fuel contains less sulphur than gasoline and is free of ethanol.
Comments from someone in western europe who drives a vehicle with DI would be helpful being that the sulphur levels of their gasoline is as low or lower than ULSD and as a result their engines can run in 'lean burn' mode.
I wonder if this will end up like modern diesels and the need to add urea solutions for the catalyst. Only here, there would be a tank to add something that would vaporize down the intake to clean the valves. If and when this is shown to affect pollution and catalyst life as the valves begin to work improperly, there will be mandated changes.
ULSD is mandatory and I've read where some believe that they expect intake deposits to be lessened due to the lower sulphur levels and the use of low/mid-SAPS oils.
If do a search on TDI, intake, build up you'll see photos of highly carbonized intakes and comments from VW mechanics who say they're getting fewer and fewer intakes to clean with the USLD switch.
Lucky for us oil burners we're ahead of the curve being that our fuel contains less sulphur than gasoline and is free of ethanol.
Comments from someone in western europe who drives a vehicle with DI would be helpful being that the sulphur levels of their gasoline is as low or lower than ULSD and as a result their engines can run in 'lean burn' mode.
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Originally Posted By: Boomer
I wonder if this will end up like modern diesels and the need to add urea solutions for the catalyst. Only here, there would be a tank to add something that would vaporize down the intake to clean the valves. If and when this is shown to affect pollution and catalyst life as the valves begin to work improperly, there will be mandated changes.
In diesels, urea solution is an exhaust treatment, not pre-ignition treatment.
I wonder if this will end up like modern diesels and the need to add urea solutions for the catalyst. Only here, there would be a tank to add something that would vaporize down the intake to clean the valves. If and when this is shown to affect pollution and catalyst life as the valves begin to work improperly, there will be mandated changes.
In diesels, urea solution is an exhaust treatment, not pre-ignition treatment.
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As the owner of a DI turbocharged car:
I won't buy another. I've had to clean my valves once already and I'm getting ready to do it a second time. It's an Audi, so I had the cam follower issue and replace that every 30k. Anal about oil.
My buddy has the same issues with his BMW DI engine. I'm not a fan.
I won't buy another. I've had to clean my valves once already and I'm getting ready to do it a second time. It's an Audi, so I had the cam follower issue and replace that every 30k. Anal about oil.
My buddy has the same issues with his BMW DI engine. I'm not a fan.
The deposits are whatever is in the blowby.
Originally Posted By: cryption
As the owner of a DI turbocharged car:
I won't buy another. I've had to clean my valves once already and I'm getting ready to do it a second time. It's an Audi, so I had the cam follower issue and replace that every 30k. Anal about oil.
My buddy has the same issues with his BMW DI engine. I'm not a fan.
How did you clean your valves the first time? BG just came out with a Direct Injection cleaner. It's different from the Induction cleaner that some owners have used.
BG GDI Cleaner
As the owner of a DI turbocharged car:
I won't buy another. I've had to clean my valves once already and I'm getting ready to do it a second time. It's an Audi, so I had the cam follower issue and replace that every 30k. Anal about oil.
My buddy has the same issues with his BMW DI engine. I'm not a fan.
How did you clean your valves the first time? BG just came out with a Direct Injection cleaner. It's different from the Induction cleaner that some owners have used.
BG GDI Cleaner
Originally Posted By: cryption
As the owner of a DI turbocharged car:
I won't buy another. I've had to clean my valves once already and I'm getting ready to do it a second time. It's an Audi, so I had the cam follower issue and replace that every 30k. Anal about oil.
My buddy has the same issues with his BMW DI engine. I'm not a fan.
Get a Lexus that has D4-S. Port & Direct Injection.
As the owner of a DI turbocharged car:
I won't buy another. I've had to clean my valves once already and I'm getting ready to do it a second time. It's an Audi, so I had the cam follower issue and replace that every 30k. Anal about oil.
My buddy has the same issues with his BMW DI engine. I'm not a fan.
Get a Lexus that has D4-S. Port & Direct Injection.
Until they figure this issue out, never again for me. My performance has dramatically dropped off. 27k miles now. I may have changed oil out too early and often though, as some are saying now this can actually cause more valve builup due to more vaporization taking place on new oil. I have no idea, I just know the drop in performance and a few mpg's is very frustrating. Now I know why my new car, stock, was beating other older cars (same car) so badly.
Winter gas.
I run no ethanol fuel mostly and my performance drop goes back to this last spring and summer. In fact, I noticed it last winter, back in january.
Originally Posted By: BMWTurboDzl
If do a search on TDI, intake, build up you'll see photos of highly carbonized intakes and comments from VW mechanics who say they're getting fewer and fewer intakes to clean with the USLD switch.
We have low sulphur diesel in New Zealand,although I'm not sure how ultra the ultra is.Our common rail direct injection diesels suffer from bad intake deposits - we clean the Mitsubishi intakes at 60,000km,as per service schedule from Mitsi.I know other Japanese engines also get the deposits too.They all have EGR....the older engines didn't get intake deposits,but EGR is commonly removed over here as we have no emission rules.Can't be done with electronic EGR.
If do a search on TDI, intake, build up you'll see photos of highly carbonized intakes and comments from VW mechanics who say they're getting fewer and fewer intakes to clean with the USLD switch.
We have low sulphur diesel in New Zealand,although I'm not sure how ultra the ultra is.Our common rail direct injection diesels suffer from bad intake deposits - we clean the Mitsubishi intakes at 60,000km,as per service schedule from Mitsi.I know other Japanese engines also get the deposits too.They all have EGR....the older engines didn't get intake deposits,but EGR is commonly removed over here as we have no emission rules.Can't be done with electronic EGR.
Originally Posted By: cryption
As the owner of a DI turbocharged car:
I won't buy another. I've had to clean my valves once already and I'm getting ready to do it a second time. It's an Audi, so I had the cam follower issue and replace that every 30k. Anal about oil.
My buddy has the same issues with his BMW DI engine. I'm not a fan.
Agreed; I'm dumping my Mazdaspeed 3 for a 128i M Sport. I love the power of the 135i, but I don't think DI is ready for prime time in any current implementation.
As the owner of a DI turbocharged car:
I won't buy another. I've had to clean my valves once already and I'm getting ready to do it a second time. It's an Audi, so I had the cam follower issue and replace that every 30k. Anal about oil.
My buddy has the same issues with his BMW DI engine. I'm not a fan.
Agreed; I'm dumping my Mazdaspeed 3 for a 128i M Sport. I love the power of the 135i, but I don't think DI is ready for prime time in any current implementation.
When did you notice your Mazdaspeed 3 dropped off? I've had my 2009 Mazdaspeed 3 GT since brand new and at around 12 to 15k miles I noticed it, and progressively became worse and worse. I'm at 27k miles now and the difference is night and day. My car used to be a wild child... now it just feels so tame and flat.
Does anyone have any more information on this new direct injection service from BG? I've had their induction service done and it didn't do much at all. In fact, I notice more of an improvement by doing a Seafoam treatment through the brake booster line than what it did. I do a Seafoam treatment before every oil change and I can tell a pretty noticeable difference in power after doing it, but the problem is in only last for a couple hundred miles before it's right back to where it was. This is what makes me believe my power loss lies with the intake valves. Otherwise the Seafoam treatments wouldn't make a difference at all.
But I am very curious as to BG's new Direct Ijection Gasoline service and what it entails. It seems like they are attacking this known problem specifically, so maybe they have come up with something genuine. Anyone done this new service or heard any testimonials, good or bad? I'm very interested as I need to find a solution to this problem.
Also, does anyone know about how much it would cost to take the car to a mechanic shop and have the pull the intake manifold etc and do the "walnut" cleaning thing or whatever it's called?
Does anyone have any more information on this new direct injection service from BG? I've had their induction service done and it didn't do much at all. In fact, I notice more of an improvement by doing a Seafoam treatment through the brake booster line than what it did. I do a Seafoam treatment before every oil change and I can tell a pretty noticeable difference in power after doing it, but the problem is in only last for a couple hundred miles before it's right back to where it was. This is what makes me believe my power loss lies with the intake valves. Otherwise the Seafoam treatments wouldn't make a difference at all.
But I am very curious as to BG's new Direct Ijection Gasoline service and what it entails. It seems like they are attacking this known problem specifically, so maybe they have come up with something genuine. Anyone done this new service or heard any testimonials, good or bad? I'm very interested as I need to find a solution to this problem.
Also, does anyone know about how much it would cost to take the car to a mechanic shop and have the pull the intake manifold etc and do the "walnut" cleaning thing or whatever it's called?
Just think of all the power and MPGs you guys were ohh and ahhing about and paid to test the DI engines. The smart money lets the other fools test the new vehicles.
Originally Posted By: shpankey
When did you notice your Mazdaspeed 3 dropped off? I've had my 2009 Mazdaspeed 3 GT since brand new and at around 12 to 15k miles I noticed it, and progressively became worse and worse. I'm at 27k miles now and the difference is night and day. My car used to be a wild child... now it just feels so tame and flat.
It's been more gradual for me. The thing has 72,000 miles on it and it is costing more to run than my 318ti and X3 combined. So much for Japanese reliability and expensive German maintenance costs...
When did you notice your Mazdaspeed 3 dropped off? I've had my 2009 Mazdaspeed 3 GT since brand new and at around 12 to 15k miles I noticed it, and progressively became worse and worse. I'm at 27k miles now and the difference is night and day. My car used to be a wild child... now it just feels so tame and flat.
It's been more gradual for me. The thing has 72,000 miles on it and it is costing more to run than my 318ti and X3 combined. So much for Japanese reliability and expensive German maintenance costs...
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