Trouble running after sitting 6 months. Dealership baffled.

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Thamnophis, Mar 24, 2021.

  1. Thamnophis

    Thamnophis New Member

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    Location:
    Iowa
    Vehicle:
    2008 Prius
    Model:
    ----USA----
    We stupidly let our 220,000 mile, 2008 Prius sit through the winter while we needed only one car - the newer Prius.
    It started up after an overnight charge (the battery was completely dead after sitting so long thru a very cold winter). It ran OK as we drove into town to get gas, but wouldnt start up after filling up.

    Had it towed to the dealer where they re-set the computer. They told me it was sending erroneous signals to the engine and after resetting the computer the car ran fine.

    Back home we started it the following day after night temps in the 40s. The electric system fires up, then after a minute the engine fires up and runs normally. After about 30 seconds though th engine starts to choke and sputter and shuts down.

    After 5 or so times of this I put the car in gear as soon as the engine kicks in and it continued to run as long as I had the accelerator depressed. As as soon as I let off the gas the engine sputtered and died again.

    I did this several times but eventually just backed out of the drive and headed down the road. After a hundred yards the engine stopped again. At this time the battery indicator showed it was on a single bar. I was able to charge the battery up to 3 bars while sitting in the drive with the car in D and my foot on the gas. But the charge quickly diminished as I started and re-started the car.

    I drove a mile, restarting the car less and less frequently the more time the engine was running. After a mile or so I was able to keep the engine running and the car charging. By the time I got to the shop (not the Toyota dealership) the car was running OK and the battery showed it was almost fully charged.

    But as this has happened now 3 times, Im sure it will be another huge hassle tomorrow morning. Anything I can help the mechanics consider? They seemed perplexed when I explained the symptoms.
     
    #1 Thamnophis, Mar 24, 2021
  2. JC91006

    JC91006 Senior Member

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    Maybe your 12v is dead? You can try resetting the car again by disconnecting the 12v battery negative for a minute and see if it'll start up normal like at the dealership
     
    #2 JC91006, Mar 24, 2021
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  3. bisco

    bisco cookie crumbler

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    stale gas
     
    #3 bisco, Mar 24, 2021
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  4. privilege

    privilege Active Member

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    I would pull the fuel line and dump half the tank into a can. then start it up again with fresh gas
     
    #4 privilege, Mar 24, 2021
  5. Thamnophis

    Thamnophis New Member

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    Location:
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    Vehicle:
    2008 Prius
    Model:
    ----USA----
    I wondered about that. I asked the mechanic and he said they'd add some gas - the tank was nearly empty when I drove it in.
     
    #5 Thamnophis, Mar 24, 2021
  6. rjparker

    rjparker Tu Humilde Sirviente

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    Your engine normally stops many times after it warms up. If it has starting problems it will have those issues as it drives. Clearly your 12v battery is history, your fuel system is highly questionable (injectors, fuel pump, bad gas) and your hv battery is likely poor.
     
    #6 rjparker, Mar 24, 2021
  7. Stevewoods

    Stevewoods Senior Member

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    A real WAG -- but:

    Does the engine need to "relearn" it's idle?

    When I had dead batteries on a couple of non-hybrid rigs in the past decade -- not the Prius -- I had some trouble with the engines stalling out until the computer relearned the idle settings -- it was particulary frustrating on my Camry and took several days to futz around with until the computer was satisfied. Symptoms you are experiencing sound somewhat similar.
     
    #7 Stevewoods, Mar 24, 2021
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  8. sam spade 2

    sam spade 2 Senior Member

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    This.
    Start with the 12 V battery, including checking the OTHER end of the main battery cables.
    Then some Gumout or Berrymans B12 in the gas.
    If it continues to act up after that, then hopefully some codes will show up.
    BUT.....do you really want to spend time and money on a car that old ??

    There are few real mechanics left anymore.......and even some of the better ones seem to know nothing about batteries and electronics.
     
    #8 sam spade 2, Mar 24, 2021
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  9. Stevewoods

    Stevewoods Senior Member

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    Have to agree with the "too few" real mechanics nowadays. A friend was having trouble with his Camry a few years back and explained it to me. I said it sounds like you need a new fuel pump.

    He took it to the dealer -- this Camry was a "pre-computer" model. The "techs" were baffled. He was told it was a very difficult problem -- made even more difficult because there was no computer to tell them what was wrong.

    He then took it to an independent shop I recommended. A family shop. The 72-year-old current owner had inherited the shop from his dad. Most of the mechanics are guys who keep their teeth next to their bed, although they have a couple of youngsters.

    The owner heard the description of the problem and said -- fuel pump.

    It was the fuel pump.

    BTW, the young guys at the shop are the ones that usually handle the hybrids! :D
     
    #9 Stevewoods, Mar 24, 2021
    Last edited: Mar 24, 2021
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