986 Boxster Smoking Issue

Helped a freind out with an emergency on Friday afternoon. Turns out his boxster started smoking excessively out the tailpipe. On most cars you would fear the worst that maybe a headgasket was blown, but the M96 engines use an oil air seperator that can go bad and allow oil vapor back into the intake stream, where it is burned off in the cylinders and causes the smoke.

Pearing up over the passenger axle, you can see the OAS attached to the side of the engine.

And from the top of the engine, you can see the top of it. There are a couple of vacuum lines that need to be removed, bolts, etc. Eventually you can wiggle it out of the car.

New OAS installed.

And the old separator out of the car.

Here is a separator that I cut open on another car to show the diaphragm failure.

This failure can cause a host of running issues. It will pop a CEL light for a vacuum leak. If bad enough, it will cause cylinder misfires and misfires damaging to the catalytic converters as well. On occasion the CEL will blink. If the CEL is blinking, turn the car off, and have it towed to a shop for repair. If the light is on solid, you can drive the car directly to a shop without damaging anything.

AOSBoxsterCELExhaustOASOil Air SeparatorPorscheSmokeWhite Smoke

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