Possible engine issues, please advise. Options

[rhodesyboy]

Hi, basically I have started being very meticulous with my celica, basically trying to see and notice everything from it to try and fix a problem before it develops.

So basically I have put my focus on ring failure as apparently this is a common problem on 3sgte engines, so I took the dipstick out and did the checked for smoke when the engine was cold after starting and then at the end of the journey and I did that in the morning journey and afternoon journey so cold air then warm(ish) air, thankfully I couldn't see any smoke even when I blipped the throttle and still no smoke so does that mean I can rest easy or can you have ring failure or at least getting towards it without smoke coming out of the dipstick?
Is there any other ways to check if the rings are gone or are about to go?

Just a couple of other little bits that get me a bit worried is that the exhaust does smoke pretty badly during cold startups (would've though just condensation from cold air but worth checking) but not when warm and there tends to be quite a strong smell of petrol on start up, also sometimes it can struggle to start so it'll sort of fire up then drop then go back up a few times before idling steadily - although this only happened once.

Also one thing that worried me was when I was checking the oil first I looked at the exhaust and there was actually a lot of smoke coming out of the exhaust when it was warm however I blipped the throttle a few times and it cleared up? it's never done this before or since.

And finally the idle is relatively rough when warm, the tachometer needle barely moves so probably doesn't change by any less that 50rpm, its not terrible but I just want to put it out there just in case it indicates something more serious.

I understand that realistically since I haven't noticed a drop in power it won't be anything serious but I just want to check that there isn't anything that I haven't picked up on
cheers

[rhodesyboy]

I just took the intake pipe off, there was a bit of grime but no actual oil, now something I did actually just remember is I'm fairly sure I was under the car and I looked up to the intake pipe and there actually was a drop of oil making its way down, the bottom of the intake pipe is split where it joins onto the turbo but not any further.
So it could very well be the turbo

Couple of things I'm remembering about my turbo, sometimes on the motorway when I'm on boost it can sound "uneven" the turbo pressure does not change and neither does the acceleration but the turbo sounds like its changing, sort of like it's spooling and then letting off then spooling again very quickly.