Brake thump - FIXED IT!!!

Thread view:

Enable EMail Alerts

Start New Thread

Thread rating:

GH - 17 Nov 2007 02:45 GMT

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 this Message

Chris D'Agnolo - 17 Nov 2007 18:24 GMT

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

>I found the problem.
>
[quoted text clipped - 20 lines]
>
> glenn

Reply to this Message

pws - 18 Nov 2007 18:45 GMT

> 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
[quoted text clipped - 3 lines]
> Chris
> 99BBB

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 this Message

Chris D'Agnolo - 18 Nov 2007 21:31 GMT

> 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

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

Chris
99BBB

Reply to this Message

pws - 18 Nov 2007 21:55 GMT

> Sorry to say I missed that! Can't you give me a youtube link ;-)
>
> Chris
> 99BBB

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.

http://www.youtube.com/watch?v=aJvEd8ssSSE&feature=related

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

http://imdb.com/title/tt0139239/

Pat

Reply to this Message

Ephar - 20 Nov 2007 17:22 GMT

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 this Message