Hi! I have a 2009 Nissan Maxima, with 96k miles; I've owned it for last three years. I use premium gasoline, and 5W30 for oil changes. It's a V6 with a VQ35DE engine. Within the last month, blueish/white smoke has been coming from the exhaust... A LOT of it! It's always present on initial start-up, but if I start the car every couple of hours or so, it's still present, but not billowing and suffocating. It also is seen when accelerating on an incline, or accelerating around a right hand turn (yes, only when turning right, not left...?!). HOWEVER..... On initial start up and drive, if I maintain speed of 35 or under (as if I were in 3rd/4th gear if I were to be driving a stick shift), there's never any billowing exhaust smoke at any point: turning, acceleration, etc, except for initial start-up. BUT if during the same "trip," I advance past 35ish MPH, to say, 65/70 on the interstate, and then slow back down off of the interstate, I get all the smoke as usual, as if my car is irritated that I went above 35MPH ;) So even if I slow down to and maintain that lower speed, I still get the smoke bc I had previously been driving at a higher speed. So that's the info on the smoke.
Here's what we've done so far: 1.) taken it to several mechanics; performed a compression test that showed good numbers for all six cylinders, with no variance between them; a leak down test, with great readings and nothing to indicate issues with valve stem seals and/or piston rings; replaced the PCV Valve; replaced spark plugs
; obviously have maintained on oil changes! No coolant
leak, checked several times. It's definitely consuming a ton of oil bc it's burning it, so we monitor that very frequently, almost daily. The car has never overheated, at least not in the last three years of my ownership. When I purchased the car, the CARFAX was clean. My car has shown no signs of any neglect in maintainence, and hasn't had any major repairs that have needed to be done, prior to this asinine situation! (I know, nothing about this makes ANY sense!!) Here's what puzzles me: when removing the intake manifold yesterday to do the leak down test, we noticed a considerable amount of oil in it!!! Like I said, we had just replaced the PCV. However, the oil seems to be coming/leaking from the PCV and into the intake.... What in the world is going on here?! Helpppppp 😩