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Aftermarket Replacement Mufflers

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Roor, Jul 13, 2023.

  1. Roor

    Roor New Member

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    Replaced muffler with aftermarket brand, not Toyota, and now my car is LOUDER than when the muffle pipe was rusted through!
    Did I loosen the exhaust manifold by removing the muffler? Thanks
     
  2. JC91006

    JC91006 Senior Member

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    If it's louder, maybe there is a leak.
     
  3. Tombukt2

    Tombukt2 Senior Member

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    Maybe the muffler is a free or flowing plate design rather than a packed design I don't know can't see it from here You mean there's a leak other than what's coming out of the tailpipe. I wouldn't think installing a muffler you could upset much not even the exhaust donut on the springs at the manifold It's made to bend 20 or so degrees but if you had rust through maybe further up the line you've got some more rust in just the pipe. So get that tweaked and you should be good.
     
  4. Georgina Rudkus

    Georgina Rudkus Senior Member

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    You probably did not loosen the exhaust manifold, because it is connected to the catalytic converter, which is before the muffler.

    The muffler is connected after the resonator chamber which is after the catalytic converter.

    This diagram might help.

    Gen 2 cat diagram.jpg

    The donut on the flange and socket should be replaced with a new one as well as tension springs. Get the genuine Toyota parts, since the universal aftermarket ones often leak.
     
  5. PriusCamper

    PriusCamper Senior Member

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    Have someone rev the engine while you inspect underneath for the source of the noise. If it's coming out anywhere other than the tail pipe than you'll know what's broken. If it's coming from the tailpipe then the muffler is either broken or designed to sound loud and annoying like that.
     
  6. TMR-JWAP

    TMR-JWAP Senior Member

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    or someone cut the cats out while you weren't looking....

    or no gasket installed at the joint. Pretty sure the donut gasket is on the muffler side of the pipe.

    Nope nope.....memory failed me....its def on the resonator side of the joint..
     
    #6 TMR-JWAP, Jul 13, 2023
    Last edited: Jul 13, 2023
  7. Tombukt2

    Tombukt2 Senior Member

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    So you didn't replace just the muffler You were put on the cat back exhaust they call it so from the flange to pipe to muffler one piece there is a gasket that goes at the flange with the two bolts then it turns the pipe has a bend in it and then there's a muffler The muffler can be installed on that pipe or it can be a slit fit in the clamp or a weld You can buy it both ways. I do believe