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Dodge 4.7 L w/ grey smoke

I have a 2010 Ram 1500 4x4 quad cab, 4.7L, 25,000 miles. When it sits for a few days, it will emit a puff of grey smoke on starting. It won’t do it the rest of the day, and even the next day, but after about 3 days, it will do it. The truck sits nose up on a sloping driveway with a slope of about 1’/20’ when parked. Truck runs great otherwise. Dealer says that this is normal for that engine, but I doubt it, as I don’t see it discussed anywhere. Is the dealer right or just trying to get me past the new car warranty?

Unless this is causing a large amount of oil consumption, you’re not going to get the dealer to fix it under warranty because they don’t consider it broken. I think, from what I’ve read here, that manufactureres do not consider oil use to be high unless their finely engineered engine is using a quart in 500 miles or less.

My guess is that it has weak valve guide seals on one or both of the rear cylinders. Maybe the others too… When a small amout of oil pools at the back of the engine on your sloping driveway, it is being drawn into the engine thru those seals by the vacuum created within the engine on the intake stroke. Does it puff smoke when parked on the level?

It only does it for a couple of seconds, and I can’t tell you if it does it on the level, because it is always parked overnight on the slope. And it only does it after sitting idle for a few days, never anytime else.

I have another remark from another source that indicates by the color (grey, definitely not with a bluish cast) that is is a leaking fuel injector that the engine then burns excess fuel upon starting after sitting idle a couple of days. I’m going to try an injector cleaner and see what happens.

From your description of the smoke as being grey rather than bluish-white the first thing I thought was fuel and not oil. When you’re out and about look around for an old oil-burning car, the kind that leaves a big puff of smoke when leaving a stoplight. If the smoke from your car is less dense than that and dissiptes more quickly then I think you’re right with the assumption it’s fuel and not oil.