Hi can someone give me any pointers, my car smokes at startup almost every start 95% of the time, its oil smoke not condensation.

Oil level at minimum, changed oil and filter to take out that possibility, changed the oil tank check valve, changed the turbo check valves, no impact at all.

I try idling for varying times no change either. Level parking, smokes even worse if parked on a slope.

This does it when cold each start and after I stop when hot for more than 5 minutes it smokes too?

Zero smoke when driving no matter how hard I push it, acceleration or trailing throttle

thanks
mike

 

"and after I stop when hot for more than 5 minutes it smokes too?"

That is not normal..
Sounds like it could be a valve seal/guide problem,,Not mentioning bringing the turbos into this which I dont know the main characteristics of that..

 

Take the boost hose of the compressor housing and look in there for oil build up in the hose. If thats clean then check the plugs. look for oil residue by the ground strap. If that's good, pull the pass side header and look up at the valve stems and the ports for signs of oil. The scavenging pump could be dieing too. to check that pull the vent lines off the oil catch tanks. the oil should never get high enough for oil to come out of the open port while it running.

 

Tim what does it mean if there is oil on the plugs / in plug wells?
My buddies had some oil when swapped the plugs

 

thanks for the guidance, will look at the scavenger pumps, although I have checked oil levels in the turbo sump a few times and its always been a thimble full. Have checked for oil from the turbos, nothing, plugs are clean. With valve seals/guides my understanding is valve guides/seals will smoke on trailing throttle and I have tested that with no smoke at all. I will have a look up the valve stems anyway.

Do you know if the scavenger pumps are driven off the engine or via the serpentine belt or water pump, never been in that part of the engine before...

cheers

 

Tim I saw in another post you said you used 'spring loaded check valves' any pointers to what you used, I was thinking about similar that opened at 3-5 psi to try to positively seal the turbo oil lines when shut off
I have new A28's on the car.

 

guys , it's a flat 6 with two turbos , not to worry

 

I recently changed out my ICs and hoses and noticed that on the old driver’sside lower boost hose (connecting the output side of the turbo to the IC) there was noticeablebuild-up of oily substance, whereas the passenger side appeared significanlt more dry.Nothing you could pour out, but I could wipe the coating off with a shop towel.

Is this cause for concern on the driver’s side Turbo?

 

Steve thanks for the reassurance, but this is a worry, a car that smokes on startup 95% of the time there is something wrong, if it was 5% of the time I an accept the 'porsche thing'.....

 

You are right to be worried. The kind of smoking behavior is uncharacteristic of the Turbo engine.

I'm not sure how to go about determining the reason for smoking. That the engine doesn't smoke under full throttle sort of clears the pistons/rings. That it doesn't smoke upon application of throttle after a closed throttle coast down sort of clears the valve stems/guides/seals.

But you have to be sure there is no smoke. You want to do the above with a low sun at your back so you can really see if there is anything visible.

But assuming the rings/rings and valve stem/guides/seals are not to blame that leaves something amiss with the vapor recovery system. I'm not up on how this works. While I'm intimately familiar with the Boxster AOS (having gone through 3 and having cut one apart) the Turbo AOS is part of the oil tank.

Unlikely there's anything amiss in that.

I have to ask though are you sure the e-level oil gage is accurate? That the engine is not overfilled with oil? For the Turbo after a 20 minute drain (at 70C or hotter) and a new filter the engine takes 7.8l of oil. This should have the oil level reading at the max line. (Note the numbers above are for my 03 Turbo based on what the techs have told me. The oil drain interval/temp is common but the amount of oil can vary. Porsche might have made a change to say the tank and the oil volume could go up or down.)

There are of course hoses that play a role and if one is cracked, pinched or not connected properly...

Next there are the turbos. The techs tell me that the turbo collector tanks when the drain plugs are removed want to drain the same amount of oil. There is the possibility one oil return line is partially blocked and the turbo is oozing oil past its seals into the exhaust.

Or then there is the possibility the turbo seals are shot.

If the vapor recovery system is suspect you might find oil in the intake system in the intercoolers.

I'm not sure how to check the turbo seals.

Does the smoke come equally from both exhaust outlets or does it favor one side? If equal this suggests a common failure and this points to a problem with the air/oil separator function.

Another thing that occurs to me is that if the smoking begins immediately upon engine start this suggests the oil is going through the combustion chambers. If the smoke doesn't appear right away this suggests it comes from after the chambers which leaves the turbo seals.

Or if the smoke comes from one side this suggests a turbo seal is oozing or leaking oil.

 

How often do you drive you car? I often get smoke on startup but I normally only drive my car on the weekend and it's sitting during the week.

 

overfilled oil is the most reason for that but in your case i would expect its the turbos

 

One of my friends driveways is silly steep, and I get smoke if I park in it. Freaked me out the first time, but it is repeatable, and happens no where else.

Tom

 

Yes but he also stated this,,
"and after I stop when hot for more than 5 minutes it smokes too?"
That sounds like theres an internal problem..



yes but he also stated this,,

 

HI many thanks to the responses, I will try to answer all the questions all together, I am so hoping there is a cause we can isolate

-The smoke is even from both sides
-The smoke comes out as soon as the engine fires
- No smoke at all on acceleration/deceleration, had the car followed as I did this
- Smokes on dead level ground, as the gound slopes more, smokes more
- Oil level running at minimum, was about 7 litres from memory to this level or less
- I have tried 5-50, 5-40, 20-50, Mobil, Rotella
- Porche filters only
- Drive the car daily, 3 or 4 starts a day at least
- I did water pipe pinning recently and changes all hoses and those from the oil tank too as well the emission valves at the back of the engine.
- leaks tested intake - all good
- fitted new bypass valves
- fitted a new 200 cell exhaust recently
- fitted new A28s recently
- fitted new turbo check valves with A28's
- fitted new oil tank check valve
- GIAC tune