4Runner 3rd gen high NOx failed Emissions my Fix!

1998 4Runner SR5 V6 with about 170,256 miles on the clock failed Colorado Emissions because of high NOx values.
Fix: 7 bottles of gas line drier Heet, and 1 bottle of Guaranteed to Pass in a 1/2 tank of fuel.
Background:
Before failed test:
Replaced both O2 sensors
New Cat, muffler, and exhaust piping
Recent oil change, with oil filer
Recent fuel filter
1/2 used air filter still good
1 year old injectors
1 year old spark plugs and wires
Newer belts
Hoses are ok
New radiator coolant
New power steering fluid
Brand new Optima battery
Else all in good maintenance condition.
1 attempted it failed because of high NOx values which means high combustion temps. Bad EGR, bad cats, poor maintenance.
Vehicle does not have EGR valve, and the cats are brand new
Also tested when the engine and outside temp was hot. Outside temp 96 degrees
Failed values:
Tested temp: 96 degrees outside
HC: 0.4222 Limits: 1.200 Pass
CO: 3.0041 Limits: 15.0000 Pass
CO2: 410.7751
NOx: 2.6018 Limits: 2.5000 FAIL
Passed Values:
Tested temp: 76 degrees outside
HC: 0.4664 Limits: 1.200 Pass
CO: 2.3501 Limits: 15.0000 Pass
CO2: 428.0696
NOx: 2.0092 Limits: 2.5000 Pass
What did I do differently? My Trick?
Changed the air filter
Tested in the morning when the outside temp was 76 degrees
Added the following to a 1/2 tank of fuel
Added 6 bottles of gas line drier Heet (Yellow bottle)
Added 1 bottle of gas line drier Heet with fuel injector cleaner (Red bottle)
Added 1 bottle of Guaranteed to Pass
Everything else all the normal suspects were recently replaced.
If you have high NOx: Go to the test station when it is cooler, make sure all your maintenance is recent, good O2, and cats, etc
If you have high HC or CO this is the usual fix:
New Air, oil, and fuel filters
Oil change
Spray the MAF with MAF cleaner
Flush your engine coolant
Pump up your tires to max or slightly higher psi (less rolling resistance)
Replace your O2 sensors
Replace your Cats and muffler
Replace vacuum lines hoses
Add 6 - 8 bottles of Heet (yellow bottle) to a 1/2 tank of fuel
Take it hot and in hot weather
I have over 30 years experience dealing with the Colorado Emissions games of passing cars and either those fixes work for me.
Once your car reaches over 25 yrs get collector plates and no more #$% emissions.
Experience:
1970 Chevelle: Full tune up, Heet, and it passed!
1983 Olds Full size with 5.0 L notorious for failing. A big name auto shop could not get it to pass. One weekend my dad and I replaced vacuum hoses, 8 bottles of Heet, new plugs and it passed!
1989 Ford Towncar in Los Angeles failed. I had a local shop replace the O2 sensor, tune up, and 6 bottles of Heet and it passed!
1998 4Runner all new sensors, cats, filters etc, with 7 bottles of Heet it passed!
After you get your car tuneup replace spark plugs and wires, oil change, new air filter, new fuel filter, new O2 sensors, new cats, and fluid changes if it still does not pass use Heet.
Good luck