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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

i think i have a cat conv problem

  • Thread starter Thread starter RedDaemon
  • Start date Start date Jan 2, 2007

RedDaemon

10 Year Member
Mar 31, 2005
3,470
9
108
Atlanta, GA
Jan 2, 2007
#1
  • Jan 2, 2007
  • #1
hey guys, i havent been around in a few days. ive been out of state on vacation and what not.

Anyway the past day since ive been home my car has developed a strange noise and i am pretty sure its something coming loose in one of my cats but i am not sure so i made a video:



there is no check engine light on my dash and the car doesnt seem to have any throttle response issues however i havent gotten on it really since i am not too sure whats going on yet. however when i accelerate from a stop i can hear that my exhaust doesnt sound right. at times it sounds like a hemi when i let out the clutch to decelerate the exhaust system underneath my car sounds like it is rattling out. the rattling you hear in the video is mild to what it sounds like when its under a load.
 

RedDaemon

10 Year Member
Mar 31, 2005
3,470
9
108
Atlanta, GA
Jan 2, 2007
#2
  • Jan 2, 2007
  • #2
bump
 

04YELLOWGT

Active Member
Jun 29, 2005
1,135
2
39
Indiana
Jan 2, 2007
#3
  • Jan 2, 2007
  • #3
Ive heard people talk about melted or damaged cats. Ive never heard a sound clip of one so I don't know but I guess its a start.
 
M

mijo_latino

Active Member
Apr 16, 2004
179
1
29
Canton, Michigan
Jan 2, 2007
#4
  • Jan 2, 2007
  • #4
definetly sounds like a cat. to me. Throw it up on some jacks, wait for it to cool, and give a light to moderate tap with your palm to each one of the converters. You should be able to find out which one if any are breaking up or loose. I recently replaced one of my cats on this magnaflow X.
 

DropTopPony

Noob Slayer
Founding Member
Aug 13, 2002
2,570
3
48
south jersey
Jan 2, 2007
#5
  • Jan 2, 2007
  • #5
yeah could be a clogged cat...i had it happen on my RX7 from running to rich.
 

RedDaemon

10 Year Member
Mar 31, 2005
3,470
9
108
Atlanta, GA
Jan 2, 2007
#6
  • Jan 2, 2007
  • #6
if its a clogged cat can i just let it take its course and burn up or should i actually do something about it?
 

04YELLOWGT

Active Member
Jun 29, 2005
1,135
2
39
Indiana
Jan 2, 2007
#7
  • Jan 2, 2007
  • #7
I think if that happens you actually need to replace it.
 

SaleenGT2001

Well-Known Member
Jul 18, 2005
2,811
4
58
Four Oaks NC
Jan 2, 2007
#8
  • Jan 2, 2007
  • #8
it will stop up your exhaust if it burns up. get an O/R pipe and be done with it.
 

DropTopPony

Noob Slayer
Founding Member
Aug 13, 2002
2,570
3
48
south jersey
Jan 2, 2007
#9
  • Jan 2, 2007
  • #9
when mine went bad it actually clogged and stopped flow...i gutted it out...if it happened on my mustang i'd just get an off road pipe.
 

fast97gt

Active Member
Jan 2, 2007
1,082
2
49
north carolina
Jan 2, 2007
#10
  • Jan 2, 2007
  • #10
cat problem

um yea your cats definitly bad do like i did little pricey but blows the rest out of the water (bbk,mac) get a basani o/r xpipe w/ cats and if you dont live in a polution controlled state like cali. have a shop remove the cats and get mil elims. for the check eng. light and enjoy that hellashish noise youll enjoy making for years on end:
 

RedDaemon

10 Year Member
Mar 31, 2005
3,470
9
108
Atlanta, GA
Jan 2, 2007
#11
  • Jan 2, 2007
  • #11
well in my state i need the cats for inspection so an o/r pipe isnt a choice

if it is a clogged cat that needs to be replaced i will probably buy a full slp mid pipe so i can replace the cats without having to deal with this again

if i do get an slp mid pipe i could always get the race pipes that go along with it.

its only been on the car for about 2 years now. would i not get anywhere by calling up BBK? 2 years seems pretty short dont you think?
 

04YELLOWGT

Active Member
Jun 29, 2005
1,135
2
39
Indiana
Jan 3, 2007
#12
  • Jan 3, 2007
  • #12
Its always woth a try. If its only been two years I would call up and start bitching but that me.
 
D

Dragstr05

New Member
Dec 21, 2004
643
1
0
Stafford VA
Jan 3, 2007
#13
  • Jan 3, 2007
  • #13
Do you have a CEL? You mentioned BBk so I'm assuming you have a midpipe on already...are you already using MILs? If you dont have MIL's on the car, a cat that sounds like that should set a code. Atleast thats what common sense tells me.

I had a bassani catted x on my car for a long time and it developed a sound exactly like that that just got worse and worse. I figured it was the cat breaking up as well (no MIL's on the car, had a CEL), and I wanted the o/r sound anyway, so I got a mac o/r h and swapped it out. When I got the bassani x on the ground, I noticed it was actually just the heat shield around the cat, and the cat itself was fine. Just the way it was broken and how close the midpipe was to the body of the car, I didnt even notice. Check your heat shields.
 

RedDaemon

10 Year Member
Mar 31, 2005
3,470
9
108
Atlanta, GA
Jan 4, 2007
#14
  • Jan 4, 2007
  • #14
ill be checking it this weekend. that is the first thing i will be checking for
 

d98gt

Founding Member
Mar 14, 2002
4,505
59
204
SE Texas
Jan 4, 2007
#15
  • Jan 4, 2007
  • #15
How much are replacement cats anyway? I have a catted h pipe that seems to have a slight rattle on the left cat. It doesn't sound too good at 2100-3000 rpms, but after that it goes back to "normal".
 

fast97gt

Active Member
Jan 2, 2007
1,082
2
49
north carolina
Jan 4, 2007
#16
  • Jan 4, 2007
  • #16
cats

um replacement cats arent that bad unless its the very front ones then you can delete that one as long as you have one between the first and last o2s sometimes it wont hurt anything but if it was like mine and had six cats that sucks if you got to have all six in your state but in north carolina you only need one per side and it only has to appear that its there it dont have to functional but i think loudmouth by slp sounds awful, id leave slp for gm and go basani or steeda stuff, bbk and mac are alright bu dont last aslong
 

fast97gt

Active Member
Jan 2, 2007
1,082
2
49
north carolina
Jan 4, 2007
#17
  • Jan 4, 2007
  • #17
cats

and i forgot to mention catted o/r pipes work ok to cause they only have one cat per side:SNSign:
 
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