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2010 Prius, very loud hum from AC

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by TheLandYacht, Dec 10, 2020.

  1. TheLandYacht

    TheLandYacht Member

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    So...on a video I recently took while diagnosing the "Cold start shudder", the beginning of the video catches a sound that I find unusual, having never driven a vehicle with an "electric compressor" AC.

    The first 2-3 seconds of the video, after starting the vehicle but before the engine kicked in. I'd had the AC on the prior night, so that sound was evident. I quickly turned off the AC so we could hear the "shudder" when the engine started, so you only get a second or two of the AC noise.

    Whatta ya think, guys? Is this a "normal" sound for the Prius AC? It's not the blower-motor so I would have to assume that it's the compressor itself? It goes away if I turn off the AC but leave the blower on.

     
  2. orenji

    orenji Senior Member

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    Yes that’s a normal sound - sometimes it will be louder and other times not. How many miles on this car?
     
  3. TheLandYacht

    TheLandYacht Member

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    130k(ish)
     
  4. orenji

    orenji Senior Member

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    Did you already post on the rattle in another thread?
     
  5. TheLandYacht

    TheLandYacht Member

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    yep

    EGR cooler was 100% clogged
     
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  6. orenji

    orenji Senior Member

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    Yes - should be done before 100k miles. Hopefully the oil use can be controlled at this point - try 30 weight or 40 weight - it will help.
     
  7. TheLandYacht

    TheLandYacht Member

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    I bought a 10 year old car from a dealer essentially sight-unseen based entirely on the CarFax (which looked good). It drove nicely & everything seemed normal. Wanted a Prius, live in the country so I have to drive into the city, plan on spending the night...and plan on buying the car I've come to look at, because it'll be gone 24 hours after I say "no" to the salesman.

    Started giving me trouble about a month in, various symptoms...and the oil (when I changed it) was black as sludge (although not as thick, thankfully).

    I have a feeling the CarFax was fudged because this car was NOT maintained well.

    Hard lesson learned. C'est La Vie, I guess.
     
  8. orenji

    orenji Senior Member

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    Buying any 10 year old car is risky. If the Carfax looked good it was probably maintained by the book. But for most of us on Priuschat we have learned things that Toyota does not advise on or mention. Like oil changes at 5k miles, tranny dump and fill, EGR cleaning. They really are great cars, but need to be treated well above what the dealer says. Good luck with you car.
     
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  9. TheLandYacht

    TheLandYacht Member

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    I've gone up to 5w20 so far (1st oil change). next one is coming up in a bit over a month.
    Also, ran 2 cans of of BG 44k over the course of a month.
    Next, BG EPR (before oil change) & MOA (during)...all of those at advice received in that thread.

    I was losing about 1/2qt per fill-up (I put about 400 miles/week on this car) prior to oil change & 44k, I'm down to less than 1/4qt...maybe the next step(s) will mitigate it even more. That'll be in about 5 weeks.

    I've been told that once it starts, there's no stopping it...so all you can do is mitigate it.
     
    #9 TheLandYacht, Dec 10, 2020
    Last edited: Dec 10, 2020
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  10. orenji

    orenji Senior Member

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    5W increased your cold start thickness of the oil. It’s the 2nd number that more important. 20 weight is thin and maybe the reason for oil usage along with high speed driving and long oil changes.
     
  11. TheLandYacht

    TheLandYacht Member

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    Well...the highspeed driving isn't going anywhere, I commute 40 miles each way...all highway miles over rolling hills...every night.

    As to the oil changes...that's what has me curious, after seeing that oil come out the first time.
    I WAS a Taxi Driver by trade before the Uber Crash (F3#king Uber!!!). So regular oil changes (3500 or 5000 miles, depending on the vehicle I had at the time) is ingrained enough that it's practically a religion.

    Caravans seemed to prefer a 3500 mile interval, while I could get away with 7k on my Sprinter. Good thing, that thing took 11qts of oil to change.

    For your viewing pleasure...
    Images of The Land Yacht, through the years… | The Land Yacht
     
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