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Prius C Check engine light loose fuel cap

Discussion in 'Prius c Care, Maintenance and Troubleshooting' started by bigmike600, Mar 27, 2012.

  1. bigmike600

    bigmike600 New Member

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    Picked up a new 2012 Prius C a week ago. Check engine light came on. Called Dealership. They said check fuel cap (I had not even used half a tank of gas yet so I did not put fuel in yet) and sure enough it was so loose it almost was off.

    I tightened it down until it clicked.

    The question is now....will the check engine light go off on it's own or will I have to take it in to have it re set.

    Thanks
     
  2. xpcman

    xpcman Senior Member

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    It will probably go off after you have started and stopped the car 3 times.
    For your info the loose gas cap error will happen on most if not all newer model cars.
     
  3. SquallLHeart

    SquallLHeart The Techie Guy

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    most times the car will correct itself after a certain amount of time... but you can always have it cleared sooner.
     
  4. cwerdna

    cwerdna Senior Member

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    I wonder if Toyota will ever have a separate warning light/message for a loose/missing gas cap.

    I hear that some Fords have such a light.
     
  5. SquallLHeart

    SquallLHeart The Techie Guy

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    i can't see that as practical..

    first off, the light comes on because the car sees a leak in the evap system.. most times.. sure.. it's because there's a loose gas cap.. however.. if there was a legitimate leak that's not caused by the gas cap..

    how is the car supposed to discern the difference?? so.. no.. it won't work.
     
  6. cwerdna

    cwerdna Senior Member

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    It seems as those Fords have it judging by Google searches for check gas cap light ford. I remember I've seen a pic before (or seen it on person) but can't find it now.

    I see your point but perhaps the light basically could point to both. If the driver tightens the cap or replaces it and it still is lit, then it points to an evap system problem.

    This is a little better than a generic CEL that could be one of hundreds of problems.
     
  7. dustoff003

    dustoff003 Blizzard Brigade #003

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    My wife's Tacoma routinely will have a CEL every couple of times after she fills up. I will remove and reinstall the cap them after a couple of trips the CEL will go off once the car realizes there is nothing wrong. This is quite a common thing with most autos nowadays.


    Posted from my iPhone via the Tapatalk app.
     
  8. Cerisa

    Cerisa New Member

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    It will likely not re-set itself. Just got off the phone with my Toyotal dealership where I bought my Prius brand new 8 months ago. I just got a scheduled inspection last week, so was bummed when my check engine light came on yesterday. I was told that even if I tighten the cap I'd have to bring it in for them to re-set the light. Perhaps it may do it on its own, but that's what the representative told me :)
     
  9. ztanos

    ztanos All-around Geek!

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    The majority of cars are set up to clear after a couple of cycles. This is usually between 50 and 500 miles... but not always. Run to advanced auto and clear it with their code scanner. They loan them out for free.
     
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  10. RocMills

    RocMills Active Member

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    It would quite easy
    Well, sure, you have a separate sensor for THE CAP ONLY... it's just silly to say it couldn't be done or would be impractical (especially since it does indeed seem that another manufacturer has succeeded in doing so). If tires can have individual pressure sensors, I don't see it being any huge problem to put a cap-specific sensor in a car.
     
  11. ShirLit

    ShirLit Junior Member

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    I'm going to jump in here and ask about something my husband has noticed a couple times in the early morning when he leaves for work. The PriusC is mine, but he's noticed a noise when he enters the garage in the morning (happened this am) that sounds like a quiet compressor running. He noticed the gas cap light blinking on the dash board, so he unscrewed the gas cap and he heard pressured air escape, put the cap back on and the motor-sound stopped. I have NEVER heard this! When he's hearing it, it's after the car has sat in the garage all night. We're in Tampa Florida so it is warm here - not sure if that makes any difference...? Does anyone know what this might be? The light was blinking again when I left 2 hours later but I did not hear any motor running. I'm just about at 10,000 miles so I'm going to be taking it in anyway, but I'm curious. Thanks in advance!
     
  12. Matt H

    Matt H Active Member

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    The compressor noise is probably just that. Smart entry? If you get close enough to the car with the fob, the brake hydraulic booster motor runs to charge the accumulator. It's normal for the fuel tank to hold some pressure.
     
  13. robertmaria

    robertmaria Member

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    i was told by a Kia salesman (about 75 years of age) that the trick with the Soul he was trying to sell me was to click it about four times when you put gas. i didnt buy the car although Kia offered me over $1,000 more for my Scion trade than my own Toyota dealer did. However in his honor to his age and experience i do click the gas cap about four times whenever i fillup my Prius c1 now. and obvously you cant click it past one click so i click it, release, click it, release,,, to the fourth or fifth time,,, just to make sure.
    i also kinda like how the brake accumulator pressurizes when you open the drivers door in the morning. to hear that compressor running reminds me of the Reagan years fighter jet military technology that finally trickled down to us for our ABS brakes in the 90's. honestly i hated it in my GM cars,,, now my Prius has it for ABS,,, go figure
     
  14. canta

    canta Member

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    Hyundai/KIA need to 4 click as in the owner manual. I used to have 3 Hyundai cars, and replaced 2 gas caps due to harden rubber sealant on the caps. actually bought aftermarket gas cap and need to buy original Hyundai caps again since aftermarket cap replacement triggers random check-engine ( which less than old caps).
    oh yeah, check-engine will reset itself for awhile...
    Toyota is different, just twist clockwise until "one" click at the end.
     
  15. ShirLit

    ShirLit Junior Member

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    I don't have a smart key, it's a regular key. I asked about the noise when I took it in for an oil change. The guy said it's "normal" for these cars to make noises any time day or night. Releasing the air pressure did not resolve it, however a new tank of gas did I guess.....It's been fine for this tank and I'm back to getting my normal mileage. Fluke? I guess.......
     
  16. Alexinnitro

    Alexinnitro New Member

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    A lot of cars will have to cycle through a couple tanks of gas.