blue smoke on startup/starter spins

Hi all.
New member here with a couple of questions about my 68K mile 2019 Tundra SR5 Crew Cab 5.7:
Several times in the last year my truck has released a pretty large cloud of blue smoke on start up. Then it won't do it again for months. It's been pretty cold here lately and it has gotten worse, doing it 3 mornings in a row now. With my reasonable amount of mechanical aptitude, I figure something is sticking in the valvetrain or I've got a bad valve seal(s). Anyone else experience this issue?
Another thing that happens occasionally is when the key is turned the starter spins like crazy, but the engine isn't starting. The starter will continue to spin without the engine starting up as long as I leave the switch on, until I turn the key back off. After 5 or 6 times, the engine will start normally. Any ideas will be appreciated.

 

is yours FFV by chance?

 

No flex fuel.

 

hm, ok your symptoms sound like the alcohol density is off but that's only in FFV

 

It's common. Many do this and worry us.

It's been a while since mine has done the cold start smoke thing.

 

I don't know if that makes me feel any better or not.
Thanks.

 

Blue smoke means oil was getting to combustion area. If you always gaet a small amount of smoke it can be several things. If it only does it at startup, it is usually coming in via the valves.

 

Valve stem seals tend to cause a small amount of blue smoke in the mornings. Someone on this board had a similar issue though and he said his ended up being the PCV valve.

 

Posting regarding the PCV - Occasional blue smoke upon start up w/ 5.7L? | Toyota Tundra Forum

 

I also experienced intermittent blue smoke on startup, but only under the following conditions:

Heavy throttle/high RPM (>3000) interval followed by less than 10 minutes of easy surface road driving before parking for long enough for the vehicle to cool down completely.

I used to have a commute that ended with exactly these conditions- accelerating to merge onto a 70-80mph high traffic highway, exiting the highway after a half mile, and parking almost immediately off the highway for the day.

I experienced it several times when I had to accelerate exceptionally hard to merge and then did not drive until close of business that day.

My commute has changed and I have not experienced it in two years and roughly 20,000 miles.