Hello Volvo Forums. This website has helped me a lot when googling questions about my new-for-me Volvo S70 2.0T (B5204T2 132kW) and I am grateful for that.
But yesterday I've got my poor Volvo towed to my garage and I am wondering what could've caused me such engine failure.

Little back-story about my Volvo, it's a 1998 S70 with 2.0T 132kW Engine.
The B5204T2 (132kW) has had injectors replaced and M4.4 was remapped around five times until we got it right. It was pushing around 0.8bar of Boost and I was running it on pure 98 Octane Petrol fully stock.

I've driven it like this for about 2000km and then one evening when doing a 3rd gear pull I noticed a lot of thick white smoke after letting of the throttle. No smoke when driving calmly, no smoke after RPMs drop to nominal range, just right after boost it would fill the whole street with white smoke.. and then after 5 more kilometres it just started dumping white and bluish smoke when idling.
I have shut off the engine, waited for it to cool down, checked the Oil Level - some was still there, but whole engine bay was dripping oil, hood was all in oil, firewall had oil dripping, looked like the whole compression went to the bottom of the engine and started pushing oil from every crevice.
The next day after almost 12 hours of the car just sitting I started it up and I've noticed that it was a bit "lumpy". It responded to throttle like it should, but I felt like it was running poorly, but... there was no smoke (stopped, idling and a reving up without driving).
Then just as I started driving home: 2nd gear, 3rd gear, Cannot see the car behind me anymore - only blue/white/gray smoke.

Towed it home, let it cool down just a tiny bit, removed the air intake, checked the turbo - Good as new, bit of oil residue, turbine shaft has no play, back and forth it does not move, up and down it has maximum of 0.5mm of play.
Took out the Spark plug cover, started undoing the spark plugs:

1st. Soaked in oil, dripping wet,
2nd. Soaked in oil, dripping ...
3rd. All Oil, like if the sparkplug got dumped into an oil pan.
Then 4th and 5th were clean, dry and "brownish"

Now the question:
Could I with a worn engine, bad re-map and 98 octane burn through all 3 pistons? Or did my rings just fail at the same time?
Could Valve Stem Seals cause this ?

Thank you for any response or thoughts. Will test compression this week when I find somewhere to rent the tool

 

Really? No. You have damaged something by pushing the engine or turbo too far. I know it was fun, but now you have a pile of parts - but with enough money could it be fun again.

 

Thank you for the reply. I'm looking at one 2.3T5 184kW Engine that is from a parts car at my friends. Should be plug and play with my M4.4 setup that I am currently running! Just.. no more Volvo for some time