Failed Smog: Doing a drive cycle after a code reset for smog test.

Hello, I have a 2002 Prius and it occasional throws an Evap Error (P4550 I think). Well, unfortunately after about 8 months of no CEL it codes again about a week before I have to smog the car, I then removed the code with my OBD2 scanner I have. Being stupid I thought enough time had passed so I went to get the smog check and It failed, it still shows the Catalytic Converter is "Not ready yet" to be scanned by the OBD2. I've been told to drive the car on the freeway (around 50-60 mph) for a while to help the computer get ready for the scan. I've read it could take 100 miles of driving also. I drive about 12-14 miles a day and Ive tried driving on the freeway more often,but of course here in So Cal Freeways can be stop and go so I have to pick a non congested one. How long should It take for the computer to set the CC so it can be read? I have no leaks and I'm not sure why it codes but ive been told its a minor code which could be because the gas cap comes loose or other minor (but expensive) things. I have 2 months before I need to send in the smog cert, so I have time, I was just wondering. Anyone have a time frame of when I could take it for a smog, or how I should drive it so the computer reads the OBD2 to scan the CC to allow the smog a little quicker? Thanks.

 

Okay well I drove a lot of Freeway miles this weekend and it made the car Smog ready. So a lot of freeway miles is key in this. Passed smog, hopefully no more issues any time soon.

 

Well, I reset the computer (removed check engine light) about a week before I needed my smog and then drove it allot last weekend after it showed not ready still. I would say about 100 miles all together (though about 40 freeway miles). The smog guy said it was the freeway driving (constant 40-60 mph for around 10 minutes and then repeat) that did it for the reset. I usually don't drive the freeway so I guess that's why it took so long.