Lots of black smoke at WOT kickdown

[jsrbrown]

Wondering why. Also seems to have lost a bit of performance. Coils were replaced with updated ones in early 2011. Did the plugs at the same time. New air filters.

No CELs.... puzzled. I'm just over 105,000 miles.

Anyone else have this issue?

[clarksongli]

check your driver side intercooler pipe (infront of driver side wheel), most likely is full of oil.

the evap setup vents to the driver side turbo.....over the years it will fill with oil, and in general vapor will make it's way to the combustion chamber and burn.

Is your oil consumption still low? the other point i might be concerned with are the turbo seals on the bearing housing. As that bearing wears, the tolerance loosens and allows some to bypass into the exhaust and burn.

i would suggest valve seals as well, but i have yet to see someone with a valve seal issue.

let us know what you find

[RFM]

Black smoke indicates a too rich mixture, usually too little air, too much gas or both. The fact that there is no error code displayed is because during acceleration and WOT Lambda1 values are left for a short period of time, in other words the system is switched in open loop for a few seconds. To accelerate there is need on a richer mixture than Lambda1. If the DME is not chipped, inner pollution can cause such issues. The current values can also be measured under the same conditions as indicated by you with appropriate equipment and trained personnel in this matter.

[jsrbrown]

Thanks for the replys. I'll check out the intercooler pipe when its not 20 degrees out. :-) My oil comsumption is in line with what others report. About a quart every 600-1000 miles. Good point about valve guides and running richer over the long haul won't do the seals any favors either.

RFM what do you mean by inner polution? When my battery started to give me performance issues last year the SA where I bought it suggested hooking it up for a good cleaning of the fuel system and oiling system. I didn't bite as they wanted nearly a 1000 dollars to do this.

My Pig is stock except for removal of the secondary cats.

[RFM]

With inner pollution i mean, fuel system of pumps to injectors, in. and exh. manifold (ports), valves, etc., oil system. I do not claim that this is the solution, but it could. Therefore first seek advice and do tests, as described in my previous post, before and after cleaning.

[jsrbrown]

RFM, that's what I thought you meant. Thanks. I'll explore that avenue as well..... while on that subject has anyone used Seafoam on their Pigs? I tried it on my Ferrari with good results.

Edited January 25, 2013 by jsrbrown

[royxaxa]

wow i did not know you could seafoam a Ferrari!

I was trying to use seafoam in my CTT but could not find a proper way to introduce it into the system. I am using the IPD plenum and there is no way to put the red tube in there before the throttle body.

I seafoamed my wife's weekend driving audi TT and boy there was a lot of smoke.

[lonertic]

check your driver side intercooler pipe (infront of driver side wheel), most likely is full of oil.

the evap setup vents to the driver side turbo.....over the years it will fill with oil, and in general vapor will make it's way to the combustion chamber and burn.

Is your oil consumption still low? the other point i might be concerned with are the turbo seals on the bearing housing. As that bearing wears, the tolerance loosens and allows some to bypass into the exhaust and burn.

i would suggest valve seals as well, but i have yet to see someone with a valve seal issue.

let us know what you find

So I know it's almost been a year but I have that exact problem! My left side intercooler pipe fills up with oil over time. The other side is perfectly fine! One mechanic I took it to said I needed a turbo replacement on that side ($15k parts+labor) and while the engine's out he said he might as well replace the other turbo too!! WTF!

Can you tell me a bit more about the evap vent and how/why it's causing a buildup of oil and how do I fix it? And when it's full of oil, how do I clean it? I don't suppose Porsche recommends that I take that hose apart every few months to drain the oil buildup right?

I know the intercooler pipe is held together with a C-clip but it unclips forwards which means I normally have to remove the entire bumper to drain the oil out of the intercooler pipe.

[clarksongli]

my clip still is removeable with the bumper till on, so get under there and try wiggling it out.

Basically the oil breather setup "vents" into the driver side turbo inlet. Most car manufacturers use the engine vacuum to pull vacuum on the crankcase/valvetrain. The benefit is that it pulls gasses out and prevent early contamination to your oil.....the downfall is that the gas holds oil vapor.

When that vapor enters and is cooled, the oil drops out and eventually you have a pool of oil.....this is perfectly normal, but is annoying since it pools in the low point of the intercooler piping.

I always drain the pipe every 5k when i do my oil changes. and spray some brake clean to get as much residue out as i can.

now it is POSSIBLE your turbo bearing/seals are going and causing oil to bypass, but is unlikely.

They do make "catch cans" which basically condense the oil prior to entering the inlet piping.....definitely not a bolt in application and you would need to make a "universal" one work.

[lonertic]

Awesome! thanks for that info! I know the c-clips CAN be wiggled out but it's a major pain in the butt, last time I pryed it with a flat head and it sprung off into the bumper near the fog light so I had to take the whole thing apart to find the clip. Not to mention the clip only goes in one direction which makes it hard to clip back on if the front bumper is attached.

There's was a hose going into the intercooler pipe that was lined with grease and I suspected it to be the source of the pool of oil, now that I know it's the evap vent. It could also be the turbo bearing, I know if I use a more viscous engine oil (20-40W instead of 0-15W) the oil consumption rate slows down noticeably, so that tells me it's probably not just the evap vent putting oil into my intercooler?

[clarksongli]

yeah i actually just did my oil change last night....pulled the pipe off like normal. I realized, that metal retaining clip doesn't need to come off completely....if you can wiggle just the one end that you can see over the retaining slot, the pipe will come free. Saves you time and eliminates the chance of that ring flying at you.

Definitely could be a turbo seal/bearing, but i would still say unlikely. running a heavier weight oil will also reduce the vapor going through the evap. However it sounds like you are burning oil, and the majority of this happens at the cylinder rings....

basically you have a scraper ring that is there to wash down the cylinder walls, but over time cylinder become out of round, scratches form, rings gum up. The more cylinders you have, the more surface area you have for oil to escape. That's typically why V8s have a higher allowed consumption rate than a 4 cylinder.

That being said, change your oil often, and do sample testing if needed. I've been playing with change intervals for a while now.....5k changes show very little to no wear in the oil with plenty of additive left. 7k showed more, but still within acceptable limits. 10k is where it starts to drop off.

I have 100k on my CTT, and i burn less than a quart every 10k.