I own a 1995 Nissan Hardbody XE pickup truck, 4 cylinder, manual transmission with 192,450 miles. I change the oil and the oil filter every 3000 miles. Very seldom I have to add oil between oil changes. It has been 450 miles since the last oil change and the old oil did not appear very dark, or what I consider dirty.
When I crank up the truck, there is the usual wisp of brownish smoke from the exhuast as soon as the engine begins to run. I will not see the brownish smoke again until I crank the truck the next time.
Lately, I have begun to notice a light bluish smoke from the exhaust. Sometimes a huge puff of light bluish smoke will blow out of the exhaust as soon as I press the accelerator after idling for thirty seconds or longer, like when at a stoplight. As I drive down the road, there is no evidence of more smoking. The strange thing is, I can repeat the same idling scenario at another stoplight and when I press the accelerator, it doesn't smoke. It might be several more times before the huge puff of light bluish smoke will appear when I press the accelerator.
Since I have been monitoring the light bluish smoking episodes, I recently replaced the spark plugs, plug wires, distributor cap and rotor button. Inspecting the old spark plugs, I was surprised to find each one a very dry, chalky white. I was expecting to find at least one spark plug brown or carboned up and/or wet and oily.
I conducted a "smoking" search on this newsgroup and found where someone suggested a leak in the exhaust system could possibly be the cause of their smoking problem. My exhaust system appears to be OK, but it certainly isn't new.
¿Does anyone have any advice as to what could be causing my intermittent, light bluish smoking problem after idling?Thanks in advance, Davïd Greenville, NC