exhaust temps, 1375f+ too hot?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by viciousthinker, May 13, 2025 at 3:07 AM.

  1. viciousthinker

    viciousthinker Junior Member

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    hi all… can anyone clarify or define what a normal range of exhaust temps on our third-gens would be? for reference i’m in houston, and the temps i was looking at were while driving at 50-60mph and during 70f weather… i am deriving my temps from readings of the sensors labeled

    catalyst temperature sensor 1 b1
    catalyst temperature sensor 1 b2

    i am regularly seeing temps like 1347/1270, that being sensors 1/2… is this normal? it seems overly hot to me, i was standing behind the car while it idled and the exhaust felt a lot hotter than i expected… is this overly hot? and if so, what would that be a symptom of?

    thx in advance for any insight friends!
     
    #1 viciousthinker, May 13, 2025 at 3:07 AM
  2. Tombukt2

    Tombukt2 Senior Member

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    Seems a bit high . Might look at fuel delivery .
     
    #2 Tombukt2, May 13, 2025 at 7:32 AM
  3. rjparker

    rjparker Tu Humilde Sirviente

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    There are no sensors, those temperatures are estimated. If you have a P0420 or are burning a lot of oil the cat may be getting clogged or you might look at fuel trims as Tom suggests.
     
    #3 rjparker, May 13, 2025 at 7:47 AM
    Brian1954 likes this.
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