i went up an incline and apuff of blue smoke came out of the tail pipe and the valves chattered a little,it cleared up and ran perfectly fine after that,why did it do that?
When you put extra stress on the driveline (going up hill), the engine had a little oil bypass the valves seals and get into the cylinders. When the oil burned off it came out the exhaust pipe as blue smoke. If that's the first time it happened don't worry about it, just keep an eye on the engine oil level and at the next oil change put a thicker oil grade in. IF that is not the first time you've seen the blue smoke and you've seen it occasionally when the car is "cold, first start up in the morning" have a mechanic check the engines cylinder pressures for blow by.
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