I have been told that if you keep your S-Type fuel tank above 85% the evap systems will not "test". Is that true? Thanks

 

Yes, the conditions for the test require a tank that isn't too full, or too empty, or has been recently filled, along with many other things. This will cause the monitor to stay in the 'not ready' state though, so if you are trying to trick an OBD emissions test, it will not pass.

 

No. In California you no longer need the Evap to be ready, just not throwing off errors. You can now pass with a "sorting" evap. I ask because while I was trying to get an 02 sensor to test, I noticed it was taking FORVER for the evap to test. In fact, because it took so long is cited as the reason it was dropped from emission completion. In California.

"No, the EVAP monitor does not need to be "Ready" (complete) to pass a California Smog Check. [1, 2]
The California [Bureau of Automotive Repair (BAR)](0.5.3, 0.5.15) explicitly allows the Evaporative System monitor to be in an "Incomplete" or "Not Ready" state at the time of inspection, provided all other readiness monitors have successfully cleared and passed.
Pending Codes: If you have a pending EVAP code but the Check Engine light is not actively illuminated on your dashboard, the vehicle can still pass the inspection

 

Oh then in that case you will be good. I've heard of people failing for monitors not ready. We don't have emissions in FL anymore though so I have no first hand experience with it.