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Winter Is Coming - Coolant Valve (P1121) & Inverter Pump replacement + maintenance at 200k miles

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Danny S, Nov 7, 2022.

  1. Danny S

    Danny S Junior Member

    Joined:
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    Vehicle:
    2008 Prius
    Model:
    Base
    Been reading the forum for a long time & just now signed up to get some specific advice. Huge thanks to everyone's contributions to this forum! I've read most threads on this subject but haven't found all the info I'm looking for. Thank you for any & all advice!

    Apologize in advance for the crazy long post! Thought I'd provide as much info as I can all at once vs getting tons of clarification questions for better recommendations.

    I'm in quite a pickle right now - starting to really stress out. Moved to Philly from LA for wife's school (both of us are deep in studies full-time 6 days/week) & registration on car is due a week from now, which requires passing a smog check & vehicle safety inspection. Issues: super tight budget right now, no decent hybrid/Prius-specific mechanics in the area (I've done my research :X3: one guy over the phone said: "Yeah, I have plenty of experience with hybrids! The Prius doesn't have any Coolant Control Valve!"), super tight schedule & car in use 5 days/week, I have limited experience working with cars even though I am a bit of DIY guy, I have zero instruments for car & no garage - just a surface lot in front of our apartment building, & "Winter Is Coming".

    Car's history:
    - Bought 2008 Prius Base with 117k miles off of 1st owner housewife in 2017 - car was serviced at dealership & Valvoline for oil changes.
    - Pedal modification at 28k miles, C0U & C0T recalls at 72k miles, Drive belts replaced at 82k miles, Brake fluid & Transmission fluid changed + Throttle body service at 94k miles, Water Pump replaced & coolant replaced at 107k miles - all @ Toyota.
    - Since purchase been going to same mechanic in LA (a Prius owner himself) for oil changes every 5k miles using Castrol GTX High Mileage oil & Bosch or Mobil filters + regular checks (topping off oil every now & then upon checking level in between changes). 12v Battery replaced at 134k miles. Brake pads replaced at 139k miles. New set of tires twice in 5 years.
    - I cleaned the throttle body myself at 178k miles using the t-shirt soaking method + scrubbing carefully. Cabin & engine air filters changed a couple times, lightbulbs changed many-many times (thinking there might be an electric circuit issue because headlights go out every 5-7k miles; but that & the dashboard periodically not turning on are the least of my worries right now - got used to just unplugging the 12v & religiously ordering lightbulbs).
    - Currently 199k miles on car (~43 MPG according to onboard display down from ~47 at purchase). And here comes the real issue:

    The day before we put the car on a truck cross-country I see P1121 (had the check eng light on & off a few months beforehand with P0101 until I finally got my hands on a MAF sensor cleaner to fix it & was thinking it came back on again - hate myself for neglecting this for a couple of months but I was overwhelmed with upcoming move). My mechanic was on vacation - talked to a Prius-specific shop that same day right before closing time - they recommended I change both Heater Coolant Water Control Valve & Electric Inverter Water Pump (although pink fluid swirling okay but I guess it's time already).

    I do not want to go to a dealership to fix this as they'll charge $250 for diagnostics + $500-700 for labor. But I have not decided whether I'm ready to tackle this single-handedly (have literally nobody in Philly so far) or try my luck quickly finding a decent mechanic nearby who just doesn't have experience with Priuses specifically.

    Regardless, I bought 2 jugs of Toyota's coolant from local dealership for a good price & am about to order Inverter Pump & Coolant Valve @ bochtoyotasouth - want to order everything I'll need all together for repairs & soon needed maintenance. Should I get a new PCV Valve to replace along with Pump & Coolant valve? Should I replace any of the hoses that lead to the Inverter Pump & Coolant Valve? Should I get a new Thermostat + O-ring + Thermostat Housing? If so, do I also need hoses for that? Any sense in replacing the MAF sensor or just clean it every now & then? Anything else I'm missing?

    Planning on changing Spark plugs after I get this main issue out of the way + considering Serpentine belt + Transmission fluid change. Would also love to address the periodically clicking AC & probably at some point the suspension/shocks - from what I've read on the forum, people replace the front struts to get the stability of the car back on track.

    Thanks once again to everyone who read this & for any & all advice!

    P.s. just finally tinted the windows before move because car was loaded with stuff during transportation & high chance tint will need to come off for inspection & registration :cry:
     

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  2. dolj

    dolj Senior Member

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    Personally, I wouldn't be looking to fix what ain't broke and just fix what was. Especially if time and finances are limited.
     
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  3. mr_guy_mann

    mr_guy_mann Senior Member

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    KISS. Replace the coolant valve (drive enough to set the OBD2 monitors) l, then get the car inspected and registered.

    Sure, there are a number of maintenance items that should be done at some point. Spark plugs, coolant, inverter pump, (clean) throttle body, trans fluid, etc. You don't NEED to do them before next week.

    Also, the more you try to do at one time, the more possible/likely that something goes sideways and the car don't work.

    Posted via the PriusChat mobile app.
     
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  4. Danny S

    Danny S Junior Member

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    Location:
    Philadelphia, PA
    Vehicle:
    2008 Prius
    Model:
    Base
    Thanks. Yeah, I guess I didn't make it clear enough that I am only looking to fix enough to get me past inspections at this point & later deal with preventive maintenance. I just wanted to make a list of everything that really should be done within the next couple of months - to order all the OEM parts online at once from a dealership that has great prices.

    I've done some more research over the last couple of days & decided to tackle both the Coolant Control Valve & Inverter Pump on my own since they're located right next to each other - I'll be using the headlight removal method. Made a list of all the tools I'll need + a reference list of posts here & YouTube videos to review once again the night before my battle with Goliath :)
     
  5. Danny S

    Danny S Junior Member

    Joined:
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    Location:
    Philadelphia, PA
    Vehicle:
    2008 Prius
    Model:
    Base
    Hi! Replaced the 3-way valve & inverter pump. Anxious about possible air in system. Asked in a big thread dedicated to coolant control valve replacement here: P1121 - Coolant Control Valve Replacement (with pics) | Page 9 | PriusChat

    Would value your thoughts. Thanks!