Help please.

I purchased my daughter this about a year ago. The car had an extensive carfax, and was regularly maintained. So, about 6 months ago, she comes home and says, hey the car is hanging at a given speed, and doesnt want to accelerate. I immmeadiately change the plugs, clean the egr, throttle valve, PCV..ect. Test drive, runs great. About a month later, hey dad my check engine light came on today, it almost died, and a huge plume of smoke bilowed out the back. Code reader said number one cyclinder misfire, so another set of plugs and a set of coils, it doesnt fix the problem. So I am thinking injector issues, pour Sea Foam in the tank, it gets worse, then clears up, AHHHH I think I found the problem, dirty injector, pour another can in and bam problem is back, and evntually goes away again. Now it is back again without any cleaning fluid in the tank, and while changing the oil I noticed it was low, like a quart low, the gears start turning....

Question? Could the seals on the turbo be the cause of all of this? misfire, hanging at speed, blowing smoke???

So, I am about to change the injectors, and rebuild the turbo. Wondering if I am missing something here???

The car now has 82000 miles on it BTW

Thans in advance for any feed back

 

Code check?

Its not uncommon for turbo issues on these.