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Brake thump - FIXED IT!!!

I found the problem.

It wasn't a loose battery. (good suggestion though)

It wasn't the sway bars or end links.

It wasn't the brake pads, clips, springs, pins, or calipers.

It wasn't even Britney Spears rolling around in the trunk as previously suggested.

Are you ready for this?........

It was the Catalytic Converter!!! It had apparently decided to fall apart internally. There was a large piece of what looks like ceramic flopping around inside. I became suspicious while crawling around under the car, and shook the exhaust pipe. It made some bad rattling sounds. I'd been shopping for a new cat-back system anyway, so I replaced the cat, mid pipe and muffler with a Magnaflow system. She's singing a new tune now, and not a thump to be heard.

:-)

glenn

Reply to
GH
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I have to disagree with you GH, the cat chunks might make a rattle sound when you brake but not a "thump". Are you sure that someone didn't remove Britney from the trunk while you had your back turned checking the muffler? Inquiring minds want to know ;-)

Chris

99BBB
Reply to
Chris D'Agnolo

Yes, my catalytic converter was rattling for a few seconds before a chunk of the element broke free and lodged against the oxygen sensor. On a 70 MPH highway, I suddenly had a top speed of about 15 mph. That was fun.

This was about 6 years ago and Britney would not have fit in a Miata trunk even then. Haven't you seen the movie "Go", where they are trying to put the girl into the trunk of the Sunburst Yellow M1? "Stop! It's a Miata!" :-)

Pat

Reply to
pws

Sorry to say I missed that! Can't you give me a youtube link ;-)

Chris

99BBB
Reply to
Chris D'Agnolo

Don't see one at a glance, but here is some fool riding in a Miata trunk, so maybe I'm wrong on the fitting issue.

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You should check out "Go", it was pretty entertaining. I won't offer any more spoliers, here is a imdb link to it.

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Pat

Reply to
pws

I'm surprised at the symptoms... When Bambi's Cat went I noticed certain maneuvers would cause the complete loss of power and only with backing off of the throttle would power be restored. Investigation under the car showed the Cat took the brunt of all the speed bumps in a lowered car. A Jackson (IIRC) High Flow Cat solved the power problems and I didn't hear any clunks until I shook the old converter. Now the clearance problems are solved also, so when I hit the speed bumps at more than .002 mm/hr it hits cleanly on the frame rather than the exhaust. Bambi's happy and so is my dentist (He just bought a Z3 from the proceeds! :/) Check the bolts every couple of oil changes... It's embarrassing to have them come loose in public. Enjoy the Ride! Ephar & Bambi The Original Winkin' Miata '92 Classic Red 'A'

Reply to
Ephar

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