Smoke at high revs (5500+)

[AXCM2]

Yesterday I finally took the Boxster out for a real workout. I was on a fairly tight, technical road that was mostly 2nd gear with some straightaways into 3rd gear. After about 30 minutes of this, and in a particularly tight downhill section where I was near redline, I noticed a considerable amount of white-ish smoke coming from the back of the car. I immediately shifted into 3rd, checked the brakes (they were fine) and looked for any signs of overheating or issues... and nada. She was cruising along comfortably at 3,000 RPM, temp gauge never went past just below 180 (typical for this car), no weird noises, nothing.

Considering I was in an area where there was no cell service, I decided to take it easy for the next few miles and once I got back to an area with cell service, I took her to redline a couple of times, and didn't notice a thing. No smoke, no issue, nothing.

Any ideas on what could have happened? She had been sitting without driving for about 2 weeks if that makes any difference, and I did notice a little more of a smokey start-up than is typical for this car.

[Stl-986]

Failing/failed AOS.

Also check for oil on the top of the engine if you see some it could be a few other things that wont be fun to replace while it still installed.

[NewArt]

Originally Posted by Stl-986

Failing/failed AOS.

Also check for oil on the top of the engine if you see some it could be a few other things that wont be fun to replace while it still installed.

+1 on the AOS. Your spirited drive surely contained some corners where one might imagine oil following those G forces. When the AOS is not in top shape, some oil gets piped into the intake, burns during combustion and smoke results.

[AXCM2]

Originally Posted by NewArt

+1 on the AOS. Your spirited drive surely contained some corners where one might imagine oil following those G forces. When the AOS is not in top shape, some oil gets piped into the intake, burns during combustion and smoke results.

I was hoping that wasn't the case.

What I find peculiar is that I don't get the huge smoking startup I would expect with the AOS failure, but ce la vie, as they say. I now have my first project!

[Stl-986]

It is actually a really easy thing to do. The biggest issue is with the plastic hose connectors. If you break the long one that goes to bank 2 it's not going to be a fun day. The short one is easy to replace. I always do it with the engine warmed up to get the hoses disconnected. Usually only takes me a half hour to remove & install a new one.

[AXCM2]

Originally Posted by Stl-986

It is actually a really easy thing to do. The biggest issue is with the plastic hose connectors. If you break the long one that goes to bank 2 it's not going to be a fun day. The short one is easy to replace. I always do it with the engine warmed up to get the hoses disconnected. Usually only takes me a half hour to remove & install a new one.

I think I read/saw that the updated AOS requires a longer hose to the second bank, but I don't yet have a part number.

[Starter986]

Originally Posted by AXCM2

I think I read/saw that the updated AOS requires a longer hose to the second bank, but I don't yet have a part number.

It does require a different hose. I replaced mine... didn't want to spend the ~$35 for the part... fashioned an "extension" fromn some expensive specialty auto hose (~$18 for the length I needed) using the old hose and while it worked, it looked like crap... oredered from Pelican the proper hose.

You'll want that updated hose/part.

[AXCM2]

Originally Posted by Starter986

It does require a different hose. I replaced mine... didn't want to spend the ~$35 for the part... fashioned an "extension" fromn some expensive specialty auto hose (~$18 for the length I needed) using the old hose and while it worked, it looked like crap... oredered from Pelican the proper hose.

You'll want that updated hose/part.

Thanks for the tip! I will definitely order it.

[911monty]

Originally Posted by AXCM2

Thanks for the tip! I will definitely order it.

Just FYI. The hose you need is not the hose that goes to bank 2, although due to age it could be replaced. The hose you need is the short hose that goes to the manifold at the TB. Pelican has it listed as needed part with the AOS. I just saw you have a MY2000. You may not need anything. The hose was needed to convert flat AOS on the earlier cars to the new style AOS.