Failed California emissions explain about codes or no codes

Question

1996 Chevy Cavalier 2.2L
Should error code(s) exist if vehicle does not pass California Emissions Smog test?
Will error codes exist with no check engine light on?
What if any error code for faulty ECT and engine cooling fan?


MY PRIOR QUESTION:

Your question was:

Whats cause of high CO over 25 mph?

Your question on AutoCodes.com Q&A has been answered by Reynaldo:

If the vehicle is being tested on the dyno, at 15 mph the dyno  pressurize the engine system, this is where is the was secondary ignition leak it it show up, the transmission system itself is presurized this would test the shift solenoid, at 25 mph the dyno now heatrs up the engine, this is where fuel the fuel control is tested ny means of temperature and maintaining 210 F , What causes a high CO at 25 mph you would want to check the operation of the PCV valve and the airfilter

REYNALDO,
PCV AND AIR CLEANER WERE REPLACED PRIOR TO FAILED SMOG TEST.
GOT ANY MORE ADVICE?
GAB

Answer 1

Then this is the catalytic convertor, If the engine can breathe at the 25 mile test, the catalytic is more prone to the cause of failure, At this temperature the catalytic should of lit off, what happens is the catalytic should hold 02, but your does not, Being a 1996 this does not have to set a code, this is the first generation OBD II. These vehicles when the CK ENG LT came on it would substitute that value, No manufactuer wants there CK ENGL LT to come on for every liitle problem, At low speed the 02 sensor is  accounted for and maintains a 14.7 to 1, At high speed test the 02 sensor is ignored, at 14.7 to 1 at a high speed your not going to be able to go up a hill.