OCBen

I seriously doubt it's the fuel. That would suggest a serious design flaw, in that the stoichiometric properties of all recommended available fuels in destination countries weren't taken into account. That's a screwup I would expect of a government agency (NASA's failure to do a basic metric conversion that led to the loss of the Mars orbiter comes to mind) but not from PAG.

If it were the fuel, I would expect to see all DFI cars using the same exact fuel discharging the same exact amount of soot. Simple as that. But we don't see that. In fact, the overwhelming majority of DFI cars don't have this soot problem at all, as being reported here and elsewhere. It's only a small percentage. But still, a troubling percentage.

My guess is that it's in the allowed variance of the fuel delivery/handling system (i.e. HPFPs and injectors). Although the components may meet design specifications, i.e. they fall within the ± tolerance band, the band is simply too wide. And the components that are closest to the nominal value (the sweet spot) are the ones found in the "good engines" that don't soot, and those that deviate from the nominal, though still within tolerance limits, are the components in the "bad engines" that soot.

But that would suggest a design error, because the engineers should have known to tighten the specs in order to not allow this potential problem. If they did engineer the design properly, then it's a problem in quality control with their supplier(s). If they use only one supplier for these fuel components, then there was a breakdown in the SPC system that allowed a bad batch of components to be delivered. If they use more than one supplier, some supplier needs to get his act together or be canned, which may have already happened.

You'd think they would recall the sooty engines to trace the defective components back to the culprit supplier. But if it's a supplier problem, I'm guessing they already know who it is. And don't feel the need to do an expensive recall, unless a group of you with sooty engines lawyer up and file a class action lawsuit and force PAG to do a recall. But if it's not a safety issue, I doubt it would get anywhere.

Just pure speculation here, that's all.

PogueMoHone

2500 miles, no oil usage, broken in per manual (plus a few full throttle applications after break-in) and a clean exhaust... only Chevron gas.

This is a superb car! (and I have owned a few!).

hlee1169

2009 C2S cab w/PDK, 12/2008 build, HPFP replaced with PDK software updated, after 5100 miles, I have
1. heavy soot
2. 1 quart of oil/1150 miles.

oil consumption is way higher than my previous 2007 C2S.

hlee1169

Forgot to say I use Chevron 91 exclusively.

stumil

2009 C2S Cab. 6 speed with 2500 miles. I have only burned 93 octane from my local Shell station. Added 1 1/2 quarts of oil at 2350 miles. Followed factory recommended break-in to the letter.

Off topic, just returned from Birmingham and PSDS. Can't stop smiling - can't wait to return. Instructors couldn't stop singing praises for PDK. They only stopped a little short of saying PDK cars only for next year's PSDS.

brendo

rijo - do your neighbors a favor and stop washing that car! you're bringing rain

rijowysock

says the guy from seattle...

i havent washed it in a lil bit.. ima wash tomorrow prior to my trip to NC tho.. im super **** about clean windows.

VC74

Hi, I was reading up on all these soot issues and was wondering... if it ever will taper off?
I now have 5700kms on my car, have always used 94 octane petro canada gas, just finished off my 4th liter of oil and there is way too much soot on my tailpipes and bumber. the car has bean properly broken in and ive been pushing it quit a bit now. My gas cosumption is quite high aswell 14.8l/100kms?
I was expecting better gas milage and less oil consumption after break in, but not the case.

jakes dad

2009 911S coupe
Using quart of oil every 800 miles.... Exhaust tips are black..inside and out.... Garage floor is spotted with oily moisture blown out at starting... 2200 miles on car..
Hoping things improve this Spring....

kosmo

if a car runs "too rich" would it throw a code?

rijowysock

chiming in again, qt of mobil 1 once every 800-900 miles... car is @ 10k and exhaust is black as can be all the time...

jk335

Has anyone successfuly taken the car to the dealer and had them FIX the soot issue?

At almost 10,000 I notice a lot of soot too... Just one day of driving and the rear bumper needs to be washed.

jk335

With about 10,000 miles, I notice the consumption has gotten worse. I worked with Porsche and sadly they deny there is even an issue. I add a quart and a half of oil every 2 fill ups. Or about 600 miles. And they say its normal.

I've gone through more than 14 quarts of oil. Porsche North America says this is normal consumption. My dealer agrees with me, but its like fightign city hall.

So in short, no the problem continues. And its getting even worse. My serive guy mentioned Porsche probably knows there is an issue and will recall the engine at one point once they know exactly what the issue is.

Good news though, you NEVER have to change the oil. It just consumes it and spits the oil right out in the exhaust!

kosmo

is the soot issue specifically to the DFI 09 & 10 cars? If so doesnt rule out any other part other than the fuel pump? Is there too much fuel being injected? Is the spark not "big" enough?

jk335

good point. no clue. And porsche NA will not investigate or look into the issue. This is months of testign the car. No one can explain why after one day, the entire bumper is COVERED in soot?

Again, every two fill ups, i am about a quart down on oil. If I go any longer, my engine light goes on. So to shut it off, i have been instructed by my dealer to just use one quart to top off.