Blue White from tail pipe and engine bay on start up
Hi. I have an 06 Altima with just over 204,000 miles on it. I recently got the valve cover and gasket replaced and an oil change (conventional5W30) There has been oil in my spark plug wells. I was told I might get a little smoke when I got it back but it should go away. I didn’t get any smoke for a few days and then one morning after driving it to lunch and starting it up again I got a huge plume of blue white smoke and it smelled like burning oil. I took it back to my mechanic and he said it was probably my valve seals and that it is a manageable problem. I then left the state and was about two hundred miles down the road and I started to experience what felt to me like intermittent hesitation. I got engine light a little within 100 miles P0420 ( cat performingbelow threshold that I’ve been getting on and off since April) and also P0720 (trans speed sensor) I noticed when I stopped that the oil was very low. I had to add almost 3 quarts. I took it to oreilys to have the codes checked and they referred me to a local mechanic down the street. They checked my coils and plugs and found oil in them again. They took off the cover and saw either poorly done job from the last mechanic or a bad gasket. So they replaced the gasket and said to keep an eye on the oil consumption. Trans place said it was 50/50 whether to replace the sensor or not. I opted not to. Oil consumption was still high and intermittent hesitation started about 100 miles into trip the next morning. I got about 200 the following day with continuing hesitation and the same codes coming up. Finally in a rest area I checked the oil and topped it off ( losing about half a quart + every 100 miles) and upon leaving the rest area I heard a slight clanking noice and it hesitated pretty badly. I got it across the parking lot with no more hesitation and called AAA to tow me the rest of the way that day. Towed it with a uhaul to get it to ending destination. When I got it here I took it to a mechanic who repaired the sensor and replaced the PCV valve that was full of oil. They think that is the cause of the massive oil leak and maybe the valve cover gasket failing and needing replaced twice. They said the plug wells were dry. I’ve had it back for about a week and approximately 200 miles. It had stopped smoking on start up on the drive out here, I’m guessing cuz it didn’t have any oil to burn and now that it’s holding oil again it’s smoking again. There has also been smoke coming from the engine bay from perhaps the exhaust manifold? I’m wondering if this is a serious issue I should get fixed (if financially viable) or if I’m good to put another 1000 mile on it or so before replacing anything ( or buying a new car) I have replaced valve seals in my van before with my dad when we rebuilt the engine, but I won’t be in anplace for us to work on it for another 1000 miles. The car seems to run fine other wise and I check the oil cold and hot after every trip (20-30 miles) and it is within parameters. And no engine light. Super long story but hoping for some opinions and insights thank you!!