Friday, August 13, 2010

blue smoke from exhaust

my 1994 pontiac bonneville se has started putting out blue smoke after i start it. does anyone know what that means and how to fix it?



Response:

It's caused from POOR maintenance, High Mileage, Overheating, just plain ol' neglect. Pull a valve cover and see (look) if the Oil Return Galleys are restricted with paraffin and residue. If they are clean them out and CHANGE the oil BEFORE restarting. This will slow some of the burning. Next, take a compression reading on all the cylinders. They should all be within 10 percent of each other and above 125 psi. If not, the Piston Rings are shot. Time for a Rebuild. Although rare, I have known people to use fuel additives and some of these cause "Blue Smoke" like a 2 cycle engine. You have said how many miles are on the engine or that it has had regular oil changes which should be done every 3000 miles. Or if you have to add oil and the frequency that you may add oil to it. Also check your Coolant as that too can cause "Blue Smoke" and could mean a blown Head Gasket. Best case scenario, your pissed off neighbor dumped oil into your gas tank to rid the neighborhood of Mosquitoes.