Timing chain can tick as it starts to stretch and contacts the upper guide, it can also make a ticking noise at start up from the old style tensioner starting to fail.
oil pump can tick if low oil in the pan or the crankshaft harmonic balancer bolt is not torqued correctly.
Next time I have one in the shop I’ll record it and post it here.

the small end of the connecting rod can tick due to low oil pressure because of no oil.

 

I don't know what was meant by the description, but it sounds important.

 

Around the sensor there is oil splatter that wasn't there before I drove without temp sensor. I know some about other vehicles. Ford..Buick etc... This is my first Chevy and the first car with an extensive electrical system btw. Chain of events: Car had an antifreeze leak for a few months... Got lower radiator hose and thermostat replaced...no more leak... Secondly thermostat failed open hence no temp reading on dashboard... I personally changed thermostat this time. Gauge works...a/c works all good but ran hot after short drives.. I unplugged the temp sensor to check it.......Got on highway..heard ticking like sound... Pulled over turned car off. Then got on here to see if other owners have any ideas on what needs to be checked and fixed if y'all could provide help. No offense taken. At this point if we don't get anywhere with it... I'll have to take it to a Chevy dealer who can bypass the no codes on code scanner... All feedback is appreciated anyway though!

 

Why would you think a Chevy dealer can do anything the guy down the street can't? If there is no CEL on there are no codes to be read. Did you just ignore the CEL?

This does not seem to be an electrical problem to me. I don't know what you mean by "extensive electrical system".

Your description is that of a car that terminally overheated, now the bearings are seized enough that the starter cannot turn the motor over.

 

If the coolant temp sensor still isn’t reconnected, there’s one problem.
after you changed the thermostat, did you burp the cooling system? Air bubbles trapped in there will cause the overheating problem.

 

ACDelco 131-158. This is the only thermostat you should use. All others can cause problems. Not overheat problems, but a CEL just the same. Before you go to the trouble of burping the cooling system, you should make sure you've got the correct thermostat. Otherwise you'll be changing the thermostat again, and burping it again.

 

I was thinking last night, for the money that GM dealer is going to charge , you could get a new oil pressure sensor, new AC Delco 131-158 180 degrees thermostat, fresh 50/50 Dexcool and fresh 5W30 and an oil filter .

 

That's true Oldblue but if his engine is seized then it would be a lost cause. Remember his words that it ran (hot most likely) to the point of making engine noises and smoke rising from the engine.
If I was a betting man then my money's on serious or terminal engine damage.

 

I think your probably correct, it might be the starter is oil soaked,
first I would , remove the spark plugs , then take the serpentine belt off and turn the harmonic balancer clockwise only , to see if the engine is seized.
Then if it’s free, do the aforementioned work.