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ICE always off

Discussion in 'Gen 5 Prius Technical Discussion' started by peternumber2, Jan 14, 2024.

  1. peternumber2

    peternumber2 Junior Member

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    I got my phev prius a week ago, and presumably I will hardly use the ICE apart from holidays trips. Is there anything wrong with that? Example: is the gas going to degradate after months sitting unused in the tank?

    Moreover, is the oil change interval going to be longer in my case? Does the car account for actual ICE usage?

    Thanks
     
  2. HacksawMark

    HacksawMark Active Member

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    Concerning the fuel, from page 86 in the manual: ■Notice about fuel ●For Plug-in Hybrid Electric Vehicles, fuel may remain in the tank for a long time and undergo changes in quality depending on the how the vehicle is used. Refuel at least 5.3 gal. (20 L, 4.4 Imp.gal.) of fuel every 12 months (refuel a total of at least 5.3 gal. [20 L, 4.4 Imp.gal.] over a 12-month period), as this may affect components of the fuel system or the gasoline engine.

    The car does not account for actual ICE usage regarding the oil. It's been discussed before in oil threads, but if it was my car in your situation, I would change the oil every 6 months. Over time, moisture will accumulate in the crankcase. Driving it long enough with the oil at operating temperature will boil off the moisture. A good 25 to 30 mile trip would be enough to do that. If too much moisture builds up and the oil is not changed, it susceptible to the development of sludge which is not good for the motor.
     
  3. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Maybe drive in hybrid mode (purposefully using the engine) about once a week.
     
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  4. Trollbait

    Trollbait It's a D&D thing

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    Gas degrades in a lawn mower because of contact with air and losses to evaporation. Car fuel tanks are better sealed against that, and PHEVs are likely even better. If the car goes too long without the engine running or adding fresh gas, the system should switch the HV mode to use fuel up and circulate fluids.

    The Volt could go up to two years before calling a change of the synthetic oil. GM has a monitoring system that takes into account temperatures and engine operation, but Toyota doesn't. They just use the same maintenance schedule regardless of ICE, hybrid, or PHEV. Here that is 10k miles or once a year.
     
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  5. BiomedO1

    BiomedO1 Senior Member

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    I have friends in the same situation. They bypass, force the car into HV mode for the day, at the beginning or end of every month. this ensures that everything stays lubricated and contaminates get burned out of the oil.
    Remember, the transmission, battery, tires are always working. Rotate the tires, check, clean, and keep clear the battery air intake filters.

    Hope this helps...
     
  6. ChapmanF

    ChapmanF Senior Member

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    Did they change that for Gen 5? In earlier generations, it's been "here's a list of 'special driving conditions' and if you can honestly say 'no' to all of them, you can go 10k, otherwise it's 5k".
     
  7. CooCooCaChoo

    CooCooCaChoo Senior Member

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    How many miles do you drive per month?

    Gas will start to expire in as little as 6 months. Oil has a longer life expectancy sitting in an oil pan, maybe 9-12 months.
     
  8. BiomedO1

    BiomedO1 Senior Member

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    That's true, especially that E85 crap in an open container - assuming it doesn't all evaporate by then. Today's modern cars is a closed system that get a periodic evap. testing, so less moisture and contaminates. As you drive around, fuel gets thoroughly mixed, so no separation either.
     
  9. john1701a

    john1701a Prius Guru

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    Over time, you'll discover random opportunities to fire up the ICE. That should be plenty of driving to use up a tank in 6 months. If not and holidays really are extremely rare, treat yourself to an evening at a restaurant far away with family or friends... or heck, even your significant other (gasp!)
     
  10. Trollbait

    Trollbait It's a D&D thing

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    Do those special driving conditions impact the motor oil when the car is in EV mode?

    Those conditions should only go into effect when they cover the majority of miles.
     
  11. Mr.Vanvandenburg

    Mr.Vanvandenburg Senior Member

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    Then there is probably a near dry start if the engine sits almost three months like I did last year. About like after an oil change start. I’m going to try some other oil filters besides the N1, to see if that’s it. Time consuming though. Maybe no oil filter seals well enough to prevent 0w-16 oil from draining down after that long. If I am even thinking about it right.
     
  12. ChapmanF

    ChapmanF Senior Member

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    I wouldn't necessarily call that a bad way to interpret what Toyota wrote ... only that it is an extra interpretation on top of what Toyota wrote. I just like to start off with here's what they say, and then dive into the second-guessing.
     
  13. Louis19

    Louis19 Active Member

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    Congrats for your new Prius , i'm in the same situation meaning that I hardly use the Ice apart for holydays trips . So I keep my gas tank between 1/2 full and a 1/4 full . Every 2 weeks , I run it in HV mode for 25 KM or I use the Charge mode to burn some gas and charge up the traction battery, as for oil change in my case it is 1 year around 10 000 KM
    PS when average daily outside temperature is below -10C I use HV mode frequently because heating is greater when generated by the ICE , heatpump works but it is struggling to warm up the cabin. Also use the seat and steering heater , but in your case , living in Rome , these temperatures are not usual;)
     
    #13 Louis19, Jan 15, 2024
    Last edited: Jan 15, 2024
  14. peternumber2

    peternumber2 Junior Member

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    Thanks all for your replies! Greatly appreciated!

    It seems that starting the ice now and then is the most common suggestion. I will do it...maybe charging the battery mitigates that feeling bad for the waste of gas.

    Is there a reason why ice kicks in when enabling the adaptive cruise control in a traffic jam? I tried twice today and it wouldn't even allow to switch back to pure ev ( battery at 70%)....

    For what regards the extended oil change, two issues seem to arise: first the ice excessive drying. I wouldn't expect much difference since we use 0w16...almost water...
    Second the oil degradation/moisture absorption: where does that moisture come from??

    PS I need to employ someone whose only duty is to continuously remind me why I didn't get a fully EV instead of a phev...

    PPS why don't I get email alerts for replies?? I seem to have all alerts turned on...
     
  15. Trollbait

    Trollbait It's a D&D thing

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    ICE on with cruise control is news to me.

    The numbers on the oil bottle don't have a direct relation to measured viscosity. 0w16 is almost as thick as 0w20 that went into the previous model.

    Water is an emission of the fuel combustion. It's where the hydrogen ends up. Some gets blown past the cylinder rings and into the crankcase. Humidity could also work its way in through the air intake.
     
  16. ken2023

    ken2023 Member

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    I've never seen that behavior. It was probably linked to something else and not cruise control. There are a few conditions where the ICE will start in EV mode. Turning on the window defogger is a common one for me. Others are listed in the manual: when it's very cold out and you turn on the cabin heat; when the hybrid temperature is too high (hot day sitting in the sun). And once the ICE comes on, it will stay on for a few minutes until the engine has warmed up. So something else triggered the ICE to start, and then it stayed on for a while. Note however that the dashboard will still indicate the car is in EV mode, but there's a second "EV" indicator that goes out indicating the ICE is running, so never flips to HV move and the dash won't display "HV", for the situations listed above.
     
  17. peternumber2

    peternumber2 Junior Member

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    I come from an old Alfa romeo that swallowed 10w60 like crazy...0w20 is deionized water to me....:)
     
  18. peternumber2

    peternumber2 Junior Member

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    I will try again tomorrow to enable cruise control...
     
  19. peternumber2

    peternumber2 Junior Member

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    I tried again and, as you mentioned, ICE didn't kick in. I don't know why it had started (twice in a row!)..SOC was above 70%, outside temp was cold but nothing extreme (10°C)....maybe it understood that in order to keep up with the preceding car it had to accelerate faster than what recommended for that level of combination SOC/temperature? sounds a bit too smart to me....
     
  20. vvillovv

    vvillovv Senior Member

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    turning on the windshield defroster is a sure fire way to start the engine, at least in a Gen 4 Prime.
    Switching to HV mode and pushing the Go Pedal enough will start the engine too, but you have to push the Go Pedal enough. It's a lot easier to get the engine on when it extremely cold, but it should be easy to start the engine whenever you want once you get to know some of the basics of which buttons or modes produce the results you'd like.

    I never worried about how long the gas stays in the tank,or at what level between full and empty. I've gone months at a time with 1/2 full tank and put $10 of gas in when it got to 1/4 full. And in 2014 I went a full year on the tank of gas that came with the new to me 2014 Prius Plugin.

    With all the threads here at priuschat about new owners complaining about the engines starting when they weren't expecting them too, your thread is a horse of a different color.