slicky rick

Porsche states that there is an acceptable oil consumption in its 997 dfi engines. I as an owner would like to further understand the why on oil consumption. We have heard owners with very minimal oil consumption and others with to the limit oil consumption. Where exactly is the oil coming in to be burned or pushed out of the engine? i have worked on cars practically all my life and know for a fact there are but a few places oil will go through. rings, valve guides, etc. however the boxer design might have its quirks regarding oil consumption. However, i doubt that DFI engines should consume more than the previous non dfi boxer engines unless the dfi system is injecting oil into the engine. what do other technicla guys think?

Bijan

Fahrer

DFI, itself, has nothing to do with oil consumption. The DFI engines in the 997.2 engines happen to have a different cylinder lining process than the 997.1 engines . This may be related to the reported increases in oil consumption. Some folks have indicated that Porsche has specified different piston rings for the new engines which may cause the problem.

ADias

I do not see more reports of 9A1 engines using oil than I have seen M96/M97 engines using oil.

rijowysock

i just bought 6 more qt's tonight since they had a deal for 3$/qt at local parts place on mobil1

my 997.2 consumes like no other, my 997.1 never consumed any.

i actually remember reading something that said with the new oil system it actually burns oil on purpose to aid in something... basically how our oil system increases pressure need based it does something that causes burning of the oil on purpose.. the 997.1 had a different oil delivery method.

Edgy01

Perhaps it's time to do another oil consumption poll--but ONLY for the MY0-9 and newer cars.

Base it on the same sort of poll options:

https://rennlist.com/forums/997-foru...sage-poll.html

ADias

Th DFI does not use oil by design. If anything the oil scavenging system of the 9A1 engine is superior and in no way adds to oil consumption.

Your stats are limited to 2 cars... some Porsche boxers (a few) do consume oil and many do not, DFI or not. Let me add to your stats - my last 2 911s (a 996 and a 997.2) did not use any oil.

Note: This thread will show again 2 camps - those who use oil and those who do not...

alexb76

Search, there was a LONG THREAD about this. There's definitely evidence that DFI engines consume more oil than non-DFI 997.1, although some (like ADias) have no issues.

ADias

You and some others claim that, but you have not shown proof. I see no reason why DFI engines should use more oil than M96/M97 engines do. Web reporting is anecdotal at best.

All 9A1 owners I actually know (5 people) use no oil...

alexb76

Well, your statement to the contrary is just as anecdotal and no proof either.

There's definitely more reports about higher oil consumption in 997.2 than 997.1, now if statistically that makes a significant difference across all 997.2 sold that's another story.

PS. Gotto admit it, YOU JUST LOVVE your 997.2, can't see anyone say bad things about her!

rijowysock

https://rennlist.com/forums/997-foru...sage-poll.html

DONE.

ADias

I would be reporting problems if I saw them and if they were relevant to the community.

I have been around boxer engines a long time and I know that some engines do use oil. It is not untypical to see a 911 engine use a quart /1000 miles or so. It's not a majority but some do and they have done so since the start in 1964.

The Web amplifies all problems and makes things seem worse than they are.

Some DFI engines do consume oil, the same way that all boxer engines do. There's no evidence at all that the 9A1 engine uses more oil. I know more people with M96/M97 engines with some oil consumption than I know with 9A1 engines in similarly sized population pools.

What I repeatedly see is concerted posting by 997.1 owners who have no dog on this race liberally posting about speculated DFI problems. I wonder why?

Bijan

It has been said that PAg sets the break in milage to minimise the reaction to oil consumption initially.
My car used half as much oil in the second 2,500 miles as the initial 2,500. I will be just as happy if it tapers to a very small acceptable figure in say 10,000 miles.

echere88

Followings are recent cars I drove, I think DFI might use more oils. But, I can understand that this can not be conclusive.

2005 Cayenne S - never add oil in between 10k miles interval
2000 Audi A6 4.2 - never add oil in between 10k miles interval
2006 MBZ SLK55 - never add oil in between 10k miles interval

2007 Audi 2.0T (DFI) - add 1q every 1800 miles
2009 997.2 C2S - add 1q every 2500 miles

By the way, both Audi and C2S also have more soots...

alexb76

No one disputes your knowledge of Porsches, but just browsing through threads here you can easily see there are a lot more reports of excessive oil consumption on DFI engine vs. earlier models. This was the exact same case with FSI engines on Audi when it was first released.

I totally agree that Web amplifies all problems, hence my earlier comment that more DFI oil consumption reports on a forum is not statistically significant to make a definitive statement one way or another, can just point out to reported problems here or elsewhere.

I am not sure what car the OP owns, but just look at post #5, 997.2 owner! As far my posts, I am simply sharing my experience, as I read most posts here, and I have read A LOT MORE reports about 997.2 oil consumption than 997.1, that's all!

I am free to share what I've seen around here with others. This is a forum to report issues, and ask others on their experiences, no need to get defensive when someone points out the reported cases. If you think this is not the case, maybe I should switch forums!