dfi motor carbon build up possible
03-21-2010, 01:27 PM
#31
Drifting
Does Porsche's DFI system have a special "starting" injector..?? If so its use intermittently could/might serve to "wash" the EGR and crankcase ventilation deposits away.
As I said before DFI use is only critical at or near WOT when the effective compression ratio actually approaches 12:1. At all other times an occasional "squirt" or two from the "starting" enrichment injector(s) would do the "trick".
As I said before DFI use is only critical at or near WOT when the effective compression ratio actually approaches 12:1. At all other times an occasional "squirt" or two from the "starting" enrichment injector(s) would do the "trick".
03-21-2010, 01:29 PM
#32
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wow u guys are very sensitive...carbon issue is a huge problem on all dfi motors im not saying that the the porsche 997.2 is def going to get it but look at previos post some one posted a 2008 caymen porsche with serious intake carbon...that car cant have more then a few miles..i hope the 997.2 is fixed because its a possable car i could be gettin..this whole post was to raise awarness on how people can fight it if comes about...from previous audi and porsche caymen post.never said porsche 997.2 is def getting carbon issues some people just over react..
03-21-2010, 01:36 PM
#33
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You can talk about whatever you want as long as we are crystal clear to separate rumor and speculation from facts.
You seem to be intent on creating a problem where none exists (on Porsche's). And I am perplexed on why you would want to do that? I call bull**** on your claim: "and they have serious carbon issues". That is a bald faced lie.
I am pulling the Troll Alert alarm...
You seem to be intent on creating a problem where none exists (on Porsche's). And I am perplexed on why you would want to do that? I call bull**** on your claim: "and they have serious carbon issues". That is a bald faced lie.
I am pulling the Troll Alert alarm...
03-21-2010, 01:41 PM
#34
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03-21-2010, 01:53 PM
#36
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Well, you know of only two, which isn't too many vs. hundreds of Audi/BMWs with DFI and high mielage. The VW DFI patent actually states clearly that carbon deposit is an issue.
However, I agree with you that this is a non-issue for 997.2 right now, either due to the fact there's not enough cars with high milage, or, becuase of the new head design.
However, I agree with you that this is a non-issue for 997.2 right now, either due to the fact there's not enough cars with high milage, or, becuase of the new head design.
03-22-2010, 01:52 PM
#37
Drifting
04-01-2010, 10:15 PM
#38
Nordschleife Master
For the record: photo of my car exhaust - 997.2S PDK, 2200 miles. No soot.
Last edited by ADias; 04-02-2010 at 12:25 AM.
04-01-2010, 11:27 PM
#39
Race Director
Only 2200 miles...Oh you need to get out and drive more my friend!
My solution to the carbon soot issue is more track events. My exhaust is super clean after a track weekend! I will be back to the track in 2 weeks! YES!
My solution to the carbon soot issue is more track events. My exhaust is super clean after a track weekend! I will be back to the track in 2 weeks! YES!
04-02-2010, 06:49 PM
#40
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FWIW- I am new to the world of Porsche, but spent 4 years in sales at a high volume BMW dealer and am familiar with the DFI isuues being debated. BMW found that the problems were less frequent if customers used top tier fuel with a guaranteed detergent level. The list of top tier providers is a simple search away, and this is a very easy way to help in eliminating the issue.
I just spent a few days with various Porsche NA corporate folks (we are a new dealer) and asked lots of questions, one of which was about build up due to DFI. I was told that it has not become an issue. Porsche test all of their new technologies for hundreds of thousands of miles before they ever see a production car, so I would rest at ease...
I just spent a few days with various Porsche NA corporate folks (we are a new dealer) and asked lots of questions, one of which was about build up due to DFI. I was told that it has not become an issue. Porsche test all of their new technologies for hundreds of thousands of miles before they ever see a production car, so I would rest at ease...
04-02-2010, 10:36 PM
#41
Race Director
FWIW- I am new to the world of Porsche, but spent 4 years in sales at a high volume BMW dealer and am familiar with the DFI isuues being debated. BMW found that the problems were less frequent if customers used top tier fuel with a guaranteed detergent level. The list of top tier providers is a simple search away, and this is a very easy way to help in eliminating the issue.
I just spent a few days with various Porsche NA corporate folks (we are a new dealer) and asked lots of questions, one of which was about build up due to DFI. I was told that it has not become an issue. Porsche test all of their new technologies for hundreds of thousands of miles before they ever see a production car, so I would rest at ease...
I just spent a few days with various Porsche NA corporate folks (we are a new dealer) and asked lots of questions, one of which was about build up due to DFI. I was told that it has not become an issue. Porsche test all of their new technologies for hundreds of thousands of miles before they ever see a production car, so I would rest at ease...
I do agree using a quality gasoline will help keep the engine cleaner.
However, part of the problem is at least with the PDK equipped cars is the PDK shift maps are tuned so the car does well in the Euro emissions/CO2/fuel economy tests. To do well, the tranmission is set up to shift up to the next gear at a very low rpm.
While this helps the car obtain very good numbers, for most drivers it means the engine will barely break 2K rpms. Operating the engine at this low engine speed consistently can contribute to engine deposits forming.
Sincerely,
Macster.
04-03-2010, 12:20 AM
#42
FWIW- I am new to the world of Porsche, but spent 4 years in sales at a high volume BMW dealer and am familiar with the DFI isuues being debated. BMW found that the problems were less frequent if customers used top tier fuel with a guaranteed detergent level. The list of top tier providers is a simple search away, and this is a very easy way to help in eliminating the issue.
I just spent a few days with various Porsche NA corporate folks (we are a new dealer) and asked lots of questions, one of which was about build up due to DFI. I was told that it has not become an issue. Porsche test all of their new technologies for hundreds of thousands of miles before they ever see a production car, so I would rest at ease...
I just spent a few days with various Porsche NA corporate folks (we are a new dealer) and asked lots of questions, one of which was about build up due to DFI. I was told that it has not become an issue. Porsche test all of their new technologies for hundreds of thousands of miles before they ever see a production car, so I would rest at ease...
04-03-2010, 01:16 AM
#43
Nordschleife Master
Maybe. Remember the M96 engine was new technology at one point and we all know -- some unfortunate souls more than others -- this technology over the long term proved to not be as good as we had hoped.
I do agree using a quality gasoline will help keep the engine cleaner.
However, part of the problem is at least with the PDK equipped cars is the PDK shift maps are tuned so the car does well in the Euro emissions/CO2/fuel economy tests. To do well, the tranmission is set up to shift up to the next gear at a very low rpm.
While this helps the car obtain very good numbers, for most drivers it means the engine will barely break 2K rpms. Operating the engine at this low engine speed consistently can contribute to engine deposits forming.
Sincerely,
Macster.
I do agree using a quality gasoline will help keep the engine cleaner.
However, part of the problem is at least with the PDK equipped cars is the PDK shift maps are tuned so the car does well in the Euro emissions/CO2/fuel economy tests. To do well, the tranmission is set up to shift up to the next gear at a very low rpm.
While this helps the car obtain very good numbers, for most drivers it means the engine will barely break 2K rpms. Operating the engine at this low engine speed consistently can contribute to engine deposits forming.
Sincerely,
Macster.
The only time I drive the PDK in Auto (Sport) is in fast twisty spirited drives, where the RPMs are up due to the driving style and D mode is almost telepathic, choosing gears and downshifting when braking.
04-03-2010, 01:18 AM
#44
Nordschleife Master
Just like other companies, Porsche has had it's share of problems from designs that were not adequately tested. eg. rubber center clutches, windows not adequately held in place, moving from 2.4 to 2.7 liter engines in the mid 70s was a disaster as the cooling system was not improved, the original composite rotors were a disaster. The rear suspensions on earlier Porsches could kill you in a corner on the older models.......need I continue?
04-03-2010, 05:01 AM
#45
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FWIW- I am new to the world of Porsche, but spent 4 years in sales at a high volume BMW dealer and am familiar with the DFI isuues being debated. BMW found that the problems were less frequent if customers used top tier fuel with a guaranteed detergent level. The list of top tier providers is a simple search away, and this is a very easy way to help in eliminating the issue.
I just spent a few days with various Porsche NA corporate folks (we are a new dealer) and asked lots of questions, one of which was about build up due to DFI. I was told that it has not become an issue. Porsche test all of their new technologies for hundreds of thousands of miles before they ever see a production car, so I would rest at ease...
I just spent a few days with various Porsche NA corporate folks (we are a new dealer) and asked lots of questions, one of which was about build up due to DFI. I was told that it has not become an issue. Porsche test all of their new technologies for hundreds of thousands of miles before they ever see a production car, so I would rest at ease...
I'm just enjoying the hell out of my 997.2, and sleeping just fine despite all the jabber about my grapes in the garage souring overnight.
Gary