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EVAP Monitor NOT Clearing

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by PriuSocal, Mar 23, 2023.

  1. PriuSocal

    PriuSocal Junior Member

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    Hello,

    New to the forum and was looking for a solution for this issue and found this website and hopefully can get some help from you, the experts :)

    1st time prius owner
    Vehicle: 2008 Prius
    Miles: 217k
    No CEL or Warning Lights

    Purchased it with a bad ABS accumulator pump and had all the brake codes on the dash associated with that issue but never no CEL light. I replaced the pump and codes were erased using my INNOVA 3100J OBD2 scanner and all was fine. Next thing I needed was a smog due to title transfer, made sure I drove it to reset the monitors and my scanner came back with Green checkmark for I/M readiness (meaning it's ready for smog). However, although it gives me "all systems ready" for smog, It still shows the EVAP monitor as incomplete. The smog tech said he needed the EVAP monitor to also be "ready" before he did the smog as he said passing the smog as-is would give him a "point" on his tech license ?!?!?! I was like OK and he advised the procedure to possibly make EVAP go ready:

    1. Fuel at 1/4 to 3/4 full
    2. Cold Start
    2. Drive car 50-65mpg for 15 min straight and let it coast to 1-2 mph after with no brakes
    3. Idle for about 5-10 minutes

    324 miles later, EVAP monitor still shows red and not ready. I have been on youtube and seen how some have taken up to 500 miles to reset, others have said totally different trip cycle procedures, I am aware that here in CA your EVAP monitor can show incomplete and still be able to pass smog (and i have had this issue on a Honda before and it passed with EVAP monitor incomplete) so I am not sure if I am just getting a too strict tech or ??

    Any help or suggestions with this would be greatly appreciated!
     
    #1 PriuSocal, Mar 23, 2023
  2. ChapmanF

    ChapmanF Senior Member

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    Yeah, you can find any number of different sources online telling you what the confirmation pattern should be. You know which one of those will help you as soon as you know which one is the same as what the car's repair manual says.

    Toyota Service Information and Where To Find It | PriusChat

    The organization of the manual takes a little getting used to. Confirmation patterns are included under the trouble codes you can get when a given monitor completes with a not-pass result. So that's great if you had a monitor not pass, the car gives you a code, you flip there in the manual, and there's all the stuff.

    It's less helpful when you're just waiting a long time for a monitor to complete; it hasn't failed or given you a trouble code, so you haven't got that key to flip straight to the right place in the manual. Instead, you first browse through the list of engine trouble codes until you find some to do with the EVAP system ... then you just pick one of those, flip to that section, and there's the confirmation pattern.

    There will also be information in there about what other conditions can prevent the monitor from running. If you've really been waiting a long time and it never seems to complete, one of those could turn out to be the reason.
     
    #2 ChapmanF, Mar 23, 2023
  3. PriuSocal

    PriuSocal Junior Member

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    Moderator please delete this thread as it no longer applies.
     
    #3 PriuSocal, Mar 23, 2023
  4. smwalker

    smwalker New Member

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    A CA smog check inspector has no ability to fail your vehicle if the EVAP is not complete. All he can do is do a precheck the car with a scanner and send you away. That is not a fail, that is a refusal. And that is against the rules of the CA smog check program. The state tells tech to inspect and run test on vehicles as they are presented for a test. It is not thier job to save you from a fail and the only reason they can refuse to do a test is if the vehicle is unsafe to operate.

    So if you go in for a test and they come back and say 'Sorry EVAP is not ready" what you tell them is please go ahead and run the test. If they reuse you send in a complaint to the CA BAR.

    You got an estimate for a SMOG test and that is exactly what you should have when you walk away from the shop.
     
    #4 smwalker, Jun 12, 2023
  5. ChapmanF

    ChapmanF Senior Member

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    At the same time, a SMOG test ought to be about how much the car contributes to SMOG. Hydrocarbon evaporation contributes to smog, and doesn't get measured at the tailpipe, or only happen when the car is running.

    So it kinda seems like, if they're serious about smog testing, they oughtta pay some attention to what the car tells them about its evap self test, which happens not while the car is running or while they are testing it, but 5, 7, or 9.5 hours after the car was shut off, and the results are saved.
     
    #5 ChapmanF, Jun 13, 2023
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