On cold days all engines will blow "smoke" on start up, this is condensation, similar to why the windshield will fog up on cold days but not warm days.
As engine warms up "smoke" should be less, but depending on the outside temp and humidity it might stay around but always more when engine is cold.
In general your cars computer knows best, IF(big if) the sensors and other components are working.
In 1997 the Camry's, 4 and 6cyl, switched to OBD II Trouble codes, prior to that OBD I was used, so any Camry made after 1996 uses these codes(1996 Camry V6 used ODB II, not 4cyl).
These are codes the computer will store in its memory, if something needs attention the computer will turn on the CEL(check engine light), but not for everything.
Here is a list of all the OBD II codes.
OBD-II Trouble Codes: Full List!
So first question is does your CEL light work.
When you turn on the key does it light up?
And does it go off after engine starts?
Some people remove or disable the CEL bulb before they sell a car, not honest but it does happen.
Most auto parts stores will loan you or come with you to the parking lot and read your OBD II codes for you.
(you can often buy OBD II code readers for under $50 on sale)
This might tell you if engine has been running rich or not.
The engine computer has two "modes", open loop and closed loop
When computer is in open loop mode it ignores many of the sensors, O2 sensor for sure.
Open loop is used until engine warms up, or when you have a heavy foot and WOT(wide open throttle)
In open loop computer uses preset injector and timing settings.
Closed loop gets you the best gas mileage, the computer monitors the O2 sensor for rich or lean conditions and sets injector duration accordingly.
If you notice a decrease in mileage then you might be running rich.
If you think you might be running rich I would put a can of Seafoam in the gas tank the next time you fill up or 1/2 a can for 1/2 tank.
This treatment works to clean off the injector nozzles so they spray instead of drip, which happens if they get dirty.
Dripping nozzle doesn't mix fuel with the air as well so O2 sensor shows lean condition, computer increase duration of injector being open to fix lean state, so more fuel is used.
You can pull the injectors, but outside of obvious problems there is no real way to test them.