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

Seafoam and Techron

Discussion in 'Gen 3 Prius Fuel Economy' started by mrtoofay, Sep 1, 2020.

  1. mrtoofay

    mrtoofay New Member

    Joined:
    Jul 6, 2020
    12
    11
    0
    Location:
    rowland heights
    Vehicle:
    2011 Prius
    Model:
    Three
    Hello,

    I recently pruchased a 2011 Prius with 170k miles on it. There were issues with the HV battery that is still under warranty from the guy that fixed it last, and the car is loud. But I purchased this car for work, so I can't really be that picky.

    First couple weeks were stressfull, the yellow triangle came up few times, and the car wouldn't start a few times as well. After couple trips back to the guy that warrantied his work and a new 12V battery, the car drove fine. And I mean just "fine". I can't get the car to average anything above 35mpg and the front side vibrates a little when going high speeds on a slight turn/bend. Since 3 of the tires were bad, I got 4 new tires, same thing. End up getting two new wheel bearing online for $90, and paid $90 in labor to get it swapped out. The car finally drives normal and no more loud noises from the bearings. I was hoping that the wheel bearing being part of the cause of bad mpg.

    Still couldn't get over 35mpg. So I figure it's time to clean the egr valves and cooler. I can't really spare the time for such an involving job now. Remember seeing someone here posing that a can of seafoam helped, I gave it a shot, since I had couple cans left in the garage. As soon as the seafoam tank is done, I added a 12oz bottle of Techron Complete Fuel system cleaner to the second tank. After half way through the Techron tank, I averaged 45mpg easy! On one of the 74mile stop and go trips, I did 53mpg!!! The weather has been a little cooler *90's instead of 100's* but I still had my AC on full blast.

    I finished the Techron tank and starting my non-treated 87octane tank today. Fingers crossed for the same mpgs.
     
    #1 mrtoofay, Sep 1, 2020
    Last edited: Sep 1, 2020
    RMB, Majafamily, Pulse07 and 2 others like this.
  2. mrtoofay

    mrtoofay New Member

    Joined:
    Jul 6, 2020
    12
    11
    0
    Location:
    rowland heights
    Vehicle:
    2011 Prius
    Model:
    Three
    OK, 2 tanks after the treatments.

    Brief info about myself. I used to be a business owner. With COVID19, my business has been shutdown since March. I got the 2011 Prius with 170k for just a little over $3k to make some money on the side. I have two part time jobs now. First being a US Census Enumerator, meaning I go to houses that didn't respond to their Census and knock on doors. Second being a Doordash and Postmates driver. Doesn't make sense driving my Mercedes GL to do those jobs. Before you ask, Yes, I've already made more than enough to cover the cost of the purchase of the Prius from these jobs in the first couple weeks.

    Here's the results of the two additive-free tanks after the treatments. The car feels the same as before the treatments, but there's an increase in mpg for sure. For the Census job, since I'm getting paid for milage and travel time, I take it nice and easy. I have been averaging approx 52mpg with mixed of highway and city driving. For the Doordash and Postmates job, since I want to get every job done asap to max my $/hr, I don't really look at the screens. While I am not racing through the streets, I wasn't driving like a grandma as well. I average 42mpg with a mixed of 30% hwy and 70% city streets. Impressive numbers for a history unknown car at 170k miles. At least to me.

    That to me, is a very big improvement. I was having a hard time getting over 35mpg even driving like a grandma. The only thing changed was the seafoam and techron tanks. Oh, this was also over this past weekend, where Socal temps went above 115. I was at Pomona doing my Census job on Sunday afternoon, and it was over 118 on Holt.

    Today morning, just for the heck of it, I pulled the EGR cooler pipe to see the condition. There's a lot of builtup in there, but it's not as caked-on as what some forum members made it out to be, they just flaked off with a touch of the screwdriver. I guess one of these days, I would clean the entire EGR system to see if it helps even mroe with the mpg.

    Now, if I can only get my seats to be more comfortable for driving around all day......
     
    Mrs.Diamond and RMB like this.
  3. Mrs.Diamond

    Mrs.Diamond Junior Member

    Joined:
    Feb 20, 2018
    66
    11
    0
    Location:
    Minneapolis, MN
    Vehicle:
    2009 Prius
    Model:
    Three
    Where do you live that you were able to find a 2012 for 3 k?
     
    TheeWood likes this.
  4. mrtoofay

    mrtoofay New Member

    Joined:
    Jul 6, 2020
    12
    11
    0
    Location:
    rowland heights
    Vehicle:
    2011 Prius
    Model:
    Three
    Believe it or not, Los Angeles County in Southern California. After a lot of shopping around, found this car listed for 4k. The paint is not in the greatest shape, the leather inside is still decent, no cracks. I guess the owner wanted to get rid of it for cheap due to the traction battery and wheel bearing issues. The car was not fun to drive, it was loud!!! It often wouldn't start due to the bad 12V battery and the tires were bad.

    Eventho the traction battery was still warrantied by the work that was done within the past 2 months of the purchase, he was getting tired of always going in and getting another cell swapped out. They use the car for commute, have other much better cars in the driveway. I pointed out all the work that needs to be done, gave them the numbers. (wheel bearing $500 with labor, traction battery $2k, 12V battery $250, new tires $400) and offered him $2.5k. He said lowest he would go is $3k. I just walked away. Next morning, his daugher, the person on title, contacted me through offerup and agreed to $3k.

    Another update on the mpg. Went through another tank of 44.5mpg. Today, took a drive to Temacula, 90 miles one way. the 200 mile round trip yielded 46mpg averaging 70mph.

    Oh, btw, it's a 2011.
     
    mikey_t and Mrs.Diamond like this.
  5. Mrs.Diamond

    Mrs.Diamond Junior Member

    Joined:
    Feb 20, 2018
    66
    11
    0
    Location:
    Minneapolis, MN
    Vehicle:
    2009 Prius
    Model:
    Three
    Thanks yes I saw 2011 I fat fingered when I typed. That’s an awesome find for you.
     
  6. Tekken

    Tekken Member

    Joined:
    Jul 9, 2019
    257
    77
    0
    Location:
    Los Angeles, California
    Vehicle:
    2013 Prius
    Model:
    Two
    Seafoam and Techron can't solve complete problem.

    Next, EGR cooler clean, intake Manifold clean, Spark plus change, air filter, oil change w/ 0W-20 Synthetic. Oil catch cans and HV bus bars clean, better tires and 12v battery etc.
     
    #6 Tekken, Jan 4, 2021
    Last edited: Jan 4, 2021
    Raytheeagle and mikey_t like this.