1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Heet water-absorbing product for fuel tank

Discussion in 'Gen 3 Prius Technical Discussion' started by justphilly, Oct 26, 2020.

  1. justphilly

    justphilly Junior Member

    Joined:
    Nov 18, 2018
    17
    4
    0
    Location:
    PA
    Vehicle:
    2011 Prius
    Model:
    Three
    Curious if any of you know about this product as it relates to Prius or Toyotas more generally. The conversation about "heet" came up on the Facebook wall of one of my friends. My friend is from Fairbanks AK and needless to say it can get very cold there. Folks were recommending to use Heet or Iso-Heet in the fuel on a regular basis just because she's in Fairbanks and it can get really cold there.

    From what I can find online iso-heet is mostly isopropanol and heet is mostly methanol.
    My car came with a warning (in the owner manual I believe) saying not to use any fuels containing methanol. I went and looked online and didn't see anything confirming or refuting this recommendation.
    I do not live in Alaska and have no plans to add heet to my fuel but I'm a curious person. Is it bad to add this product or other similar products to your gas? What would happen if you do?
    For those who don't know, one of the main uses of heet is to absorb water in your gas tank (it does that because alcohols in general will mix with water, even in a mostly gasoline solution) and allow it to be removed by using the car normally (fuel pump, engine, you know the rest).

    I didn't find anything on Priuschat or elsewhere online directly addressing this question.
     
  2. PriusCamper

    PriusCamper Senior Member

    Joined:
    Mar 3, 2012
    10,775
    4,372
    0
    Location:
    Pacific Northwest, USA
    Vehicle:
    2007 Prius
    Model:
    Two
    The source of this problem is that adding ethanol to gasoline means water gets in the fuel because ethanol attracts water (hydrophillic). In some states you can by no-ethanol gas, which treats the cause of the problem rather than just the symptoms.

    In general, fuel stabilizer and other similar products address the Ethanol problems which is primarily an issue with small engines like lawn mowers. Never read of anyone having problems with Prius that get diagnosed back to water in the gas. It can happen, but haven't seen it focused on here before.
     
  3. Pluggo

    Pluggo Senior Member

    Joined:
    May 23, 2016
    608
    532
    0
    Location:
    Folsom, Pennsylvania
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Advanced
    Heet sounds like what they used to sell as fuel line antifreeze. I actually did have a frozen gas line one time in an old car. I was young and didn't mind disconnecting the steel line and gently thawing it. There seemed to be just a little plug of ice in one place and it probably would have resolved on its own the next sunny day. I also lost a fuel pump on that 70s vintage car by using gas with ethanol in it. The rubber diaphragm had turned into gooey tar you could mold like putty. There's a good reason when a manufacturer specifies that your fuel must have no more than 10% ethanol. I wouldn't add another drop.
     
    PriusCamper likes this.
  4. PriusCamper

    PriusCamper Senior Member

    Joined:
    Mar 3, 2012
    10,775
    4,372
    0
    Location:
    Pacific Northwest, USA
    Vehicle:
    2007 Prius
    Model:
    Two
    Yes, when the corn lobby tried to boost Ethanol requirements above 10% auto manufacture lobby went wild on how much engine damage it would cause to their cars because it's not just the water problem, it's that ethanol builds up laminates inside the engine that can eventually cause serious damage.
     
  5. Grit

    Grit Senior Member

    Joined:
    Aug 22, 2017
    6,103
    4,032
    1
    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    Ah, the corn states. We will hear about them come the eve of nov 2.
     
  6. fuzzy1

    fuzzy1 Senior Member

    Joined:
    Feb 26, 2009
    17,039
    10,013
    90
    Location:
    Western Washington
    Vehicle:
    Other Hybrid
    Model:
    N/A
    That's exactly what it is. The original company was started just after WWII, based on the founder's military experience, back when everyone used pure gas, many decades before the ethanol mandates.

    I keep seeing conflicting claims about whether it is useful in non-freezing conditions, or merely just an extra profit maker for retailers.
     
  7. AzusaPrius

    AzusaPrius Senior Member

    Joined:
    May 27, 2020
    1,639
    766
    0
    Location:
    California
    Vehicle:
    2010 Prius
    Model:
    IV
    I have used Heet in my prius it helps in not just cold weather conditions but also in poor gas conditions.

    Your cheap station like arco may have a little too much water in their tanks.

    Posted via the PriusChat mobile app.