07 X5 3.0Si.. issues, possible waterpump??

[Mr.X5_3.0si-retired]

07 X5 3.0Si... 195k km's

*Cliff Notes*
-stopped driving as daily driver, battery died, 2 02 sensors died
-routine maintenance, front brake set up, oil change
-cat 02 error, cat deemed starting to need replacing, error goes away on it's own
-brake fluid message (still needs done)
-stage 2 L+R brakelight warning, replaced bulbs, everything works, error remains, left tailight cracked, has common water build up..
-cat 02 error comes back (going catless active autowerke downpipe this month) seems to have went away on it's own again
-rear brake system needs replaced
-floor trunk handle snapped
-winter comes loud ticking appears, freak out about lifters and $6500 quote repair, daily drive it for a week, ticking gone *phew*, possible common vanos?
-saturday (02.13) vehicle starts clunking and smoking from front end, doesn't appear to be engine (could be wrong), smells like melting, hr later drives away perfectly fine but still smells like melting (seems like left behind odor)
-drive it for a solid 1.5hrs, then do some start up shut off to see if issue comes back, does not
-next day starts up fine, no melting smell but one of the fans has a weird noise, not very loud.. dont seem to be running at super speeds
-no engine lights

*STORY*

back story goes.. we got a 2014 new at the time Dodge Ram Sport 2 years ago and the X5 has been a lemon so we stopped using it as the daily driver and started driver the Ram..
i would still start the X5 up and take it to the gym, groceries and run errands with it just so it wasn't completely left deserted..
after doing this for 1.5yrs and driving it a little less each time i ran into a dead battery and probably unrelated but 2 02 sensor errors.. fixed that and started driving it more..
it drove good for 2 months then it popped up some routine maintenance on the front brake set up, oil change, the shop suggested next time to run a brake fluid flush as the ECU was showing it was going to pop up soon but they said since it wasn't daily driven just to wait for my next appointment..
after a month i then rain into stage 2 left/right brake light warnings which i had previous and the shop fixed it but didn't mention or charge for it.. i figured i'd just replace the bulbs, did that and the warning was still there so i decided to wait until next repair was needed as i tested them and they all light up and work proper..
a month later i started getting the 02 sensor error at the cat again and still currently have so im thinking of doing the active autowerke catless downpipe as last time the mechanic said the cat was looking a bit wore out..
so fast track a few months later to winter, cat 02 error gone? start getting a tick and i figured it was the common vanos tick and so i drove it a bit to warm it up and the tick never went away, let the vehicle sit cuz i didn't wanna chance ruining the engine, (no engine light) well my wife took it for a long drive and the tick went away and has not returned..
*NEWEST ISSUE, HELP!!!!*
we took it out for an hour drive into the city, it ran smooth felt fine minus usual acceleration lag i've started to conclude as a BMW thing or the cat needing to be replace.. anyways after arriving at our destination and some shopping is done we go out to the vehicle, start it up, we here some noises like rocks banging together and the X5 starts instantly smoking from front grill area (not engine i don't believe), smelt like burnt plastic, turn off the engine and the clunking slows down and goes away.. we let it sit 15 mins try again, same issue, wait another 15 mins same issue.. we are at this point in an underground parking at a major mall so we start figuring out how were going to get the vehicle out and if were going to catch everything on fire.. after 20 mins we just say screw it were gonna drive it out to the nearest parking lot and hope we don't catch on fire.. we start it up and it drove away perfectly fine.. hit the highway for our hr long drive back and it was still perfectly fine, after stopping for dinner and at a family members house, still starting up fine.. started it up the next day, still fine but one of the fans making a weird sound, not super loud??
any idea's.. this vehicle has been a nightmare..