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Old 06-21-2006, 02:26 AM   #1
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Default Downshifting 'click' and rotten eggs?

2000 bonny se

so most of the time when i floor the gas pedal, then let go, and the transmission does a downshift, i hear a loud 'click noise'. this only happens under hard acceleration, then taking foot off pedal for a major downshift. weird, any1 experience this? any ideas how to solve? im thinking it'* the cat.

also, when i parked it in the garage and got out (with the engine still running) i smelled rotten eggs maybe the cat again? i think i read somewhere on the forums about rotten eggs = bad cat... can any1 confirm?

thanks

mike
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Old 06-21-2006, 09:11 AM   #2
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Mike..

Not sure I understand your saying about mashing and downshift. Please explain a little differently.

The rotten egg smell is typically a cat that is going or gone south.
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Old 06-22-2006, 01:58 PM   #3
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sorry if i was not clear, let me try to explain a little better.

when i accelerate, i floor the gas pedal and the tach shoots up to ~5,000-6,000rpm. Then i suddenly release the gas pedal, so the transmission downshifts and tach shoots back down to a low rpm. When this downshift occurs, i hear a loud "clank" from under the car somewhere.

This only happens during a downshift as i explained above.

BillBoost37: do you think it is time to change the cat? Is the rotten egg smell a sure sign that it needs replacement?

Thanks
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Old 06-23-2006, 09:19 AM   #4
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i talked to one of my neighbours whos a real car nut (he'* currently got a late 60'* early 70'* plymouth duster and plymouth roadrunner in his garage that are being restored). I asked him about the rotten eggs smell and if that implies a BAD cat, but he told me that means a GOOD cat? wtf?
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Old 06-23-2006, 10:16 AM   #5
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Rotten eggs are usually experienced by senior citizens that idle the car to the store and back.

Get the car up on the highway for at least 20+ miles and get on it a good bit. That will heat the cat up and should clear out the smell.

On the clunking.. you probably need to check a motor mount.
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Old 06-23-2006, 10:26 AM   #6
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Try it with your traction control off and see if it still does it. It might be that, but I could be wrong. Mine did something like that, but I would discribe it more like a buzz. Kinda felt like the antilock brakes.
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Old 06-23-2006, 10:36 AM   #7
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i have no traction control, but i'll try the highway clearing out the cat thing...

so is rotten eggs good or bad?
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Old 06-23-2006, 10:48 AM   #8
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It'* not good.
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Old 06-23-2006, 04:03 PM   #9
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wtf? now i dont know what to believe
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Old 06-26-2006, 07:59 PM   #10
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