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  • 1996 - 2004 SN95 Mustang -General/Talk-

Do Cats go bad???

  • Thread starter Thread starter hotstang_46
  • Start date Start date May 27, 2007

hotstang_46

Member
Apr 11, 2007
481
4
18
Charlotte NC
May 27, 2007
#1
  • May 27, 2007
  • #1
Recently bought an 00gt 60k and have not taken it for final registration and emissions check yet and don't know what to expect. Was just reading a different post and someone said that the cats at 95k were probably bad on the dudes car. Will i possibly have this issue. Don't know if this is pertinant or will help with the emissions, but I just replaced the fuel filter, fuel pump, plugs and ran some sea foam through an intake hose.....anything else i can do to help the car pass? Should be taking her this coming week!

thanks
 

Orange...

New Member
Aug 22, 2004
59
0
0
SASKATOON
May 27, 2007
#2
  • May 27, 2007
  • #2
um... I had the original cats on my car with 100km's on them and they were fine.
What is making you think that there is a problem with them?

If there is a problem check the exhaust temp with a heat-temp-gun (I have one and I can't even remember the correct term)... anyways... you should get higher temp readings after the cats then before them. If not then they are bad for sure.

also I'm not sure how the safeties work there but can't you take it in, and if it doesn't pass then you have like 30 days to repair it for the reinspection to be free?
 

hotstang_46

Member
Apr 11, 2007
481
4
18
Charlotte NC
May 27, 2007
#3
  • May 27, 2007
  • #3
yeah....if i don't pass it's no biggie and they'll give me a lengthy extension...but the less of my life that's wasted at the DMV the better....I think the car won't pass though, unless any of the fixes i listed above will do anything.....Right before the car was put into storage for 3 years by the previous owner it failed emissions and he just parked it......
 

Seraphitia102

will post boobie pics for a supercharger
Oct 11, 2004
737
1
16
California
May 27, 2007
#4
  • May 27, 2007
  • #4
OEM cats don't deteriorate so fast in my personal experience. I have 61,000 miles, and passed the smog check with flying colors.

My father has a 1986 Mercedes Benz 420SEL, still passes smog. It's a lot more polluting in numbers than my Mustang, but still under the legal limit. Plus, the cat is about 21 years old.
 
S

Stang_Thang

New Member
Apr 10, 2007
12
0
0
Jackson, Tn
May 28, 2007
#5
  • May 28, 2007
  • #5
Pre cat should be about 100 degrees cooler...after cat should be 100 degrees hotter
 

Wolvrin704

Member
Apr 17, 2007
120
0
17
Milford, OH
May 28, 2007
#6
  • May 28, 2007
  • #6
Cats shouldn't go bad, but if they do they are supposed to be warrantied by the manufacturer up to 100K. Did the previous owner know why it failed emissions? Thank god they did away with emissions testing here in SW Ohio, it was pretty much a joke.
 

jstreet0204

Active Member
Jun 26, 2003
939
0
36
Winston Salem, NC
May 28, 2007
#7
  • May 28, 2007
  • #7
They only time I've seen cats go bad is when they've been contaminated by excessive oil burning, oil leaks, or a blown head gasket. Then they tend to get plugged up and the car will run noticably bad.
 
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