Smoking out the exhaust is one of the most annoying problems you can run into.  In some states, you can get reported (like California) and get a ticket in the mail!  Although it might sound bad, smoke out the exhaust does not always equal instant doom.  Slight oil smoke is okay and does not automatically signal a dying motor.  Coolant smoke is always bad, as this is a sure indication the coolant system has been compromised inside the engine.  Oil smoke is typically bluish in color, but oil smoke from a rotary engine can come out white.  Oil smoke can look exactly like coolant smoke.  The difference is the smell of the smoke.  Oil smoke is acrid and burns your eyes and nose.  Coolant will smell sweet.

If the smoke is coolant, this is bad.  This is a good indication a water seal has failed internally.  Worst case, the water jacket broke on the housing, and the housing needs to be replaced.  Pull the spark plugs and check the tips, if coolant is getting in before the exhaust cycle, the spark plugs will come out clean or white; spark plugs will normally come out black with some crusty deposits.  Minimum, a rebuild is necessary.

If it's oil smoke, it is either caused by the turbo or the engine.  Oil smoke caused by the turbo will typically smoke a lot under boost.  Oil smoke caused by the engine will typically smoke under decel on throttle lift.  Pull the spark plugs and check the tips, if the oil is getting into the engine, the spark plugs will come out black with excessive crusty, black deposits.  In extreme cases, you can see traces of oil on the spark plugs tips.

• Under boost
• Decel / throttle lift

Questions?  Comments?  Send mail to:  reted@fc3spro.com

10/08/2004