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how to clean catalytic converters?

  • Thread starter Thread starter Allforspeed
  • Start date Start date Nov 12, 2005
A

Allforspeed

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Oct 25, 2004
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Nov 12, 2005
#1
  • Nov 12, 2005
  • #1
i have the stock H pipe off my car and am about to go smog and was wondering if there is any chemical i can use to clean out the cats since they look kind of black inside. i understand most of those "pass smog guaranteed in a can" things are just chemicals that clean out the cats.

please only people that have actually done this or know about it for sure, i cant afford to replace my cats if i ruin them so i really dont want to ruin my cats but i really want to pass smog also (california sucks


thanks!
 

timewarped1972

Member
Jun 17, 2004
642
0
16
mesa, az
Nov 12, 2005
#2
  • Nov 12, 2005
  • #2
about all you can do is put the pipe back on the car, maybe put some of that stuff you see in the auto stores in the tank and drive. as far as i know the best way to really do anything for them is to get them nice and hot because thats what makes them work......
 
A

Allforspeed

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Oct 25, 2004
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Nov 12, 2005
#3
  • Nov 12, 2005
  • #3
i was hoping someone out there had sprayed carb cleaner or paint thinner on them to clean them and then smogged their car so i know it doesn't ruin them, i always let em get nice and hot also, that is true

thanks!
anyone else?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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129
Nov 12, 2005
#4
  • Nov 12, 2005
  • #4
They are a thin honeycomb matrix which clogs up. Then as they clog, they start to melt. So one would have to have loose debris in there and then backflush the matrix to get the crud back out the header side.

If they are not allowing the catalyzation to occur, they should be renewed. Now that said, I have not tried any chemicals, so let's see if people have and what they say.

Good luck.
 

95COBRA241

New Member
Sep 3, 2005
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Delray Beach, FL
Nov 12, 2005
#5
  • Nov 12, 2005
  • #5
HISSIN50 said:
They are a thin honeycomb matrix which clogs up. Then as they clog, they start to melt. So one would have to have loose debris in there and then backflush the matrix to get the crud back out the header side.

If they are not allowing the catalyzation to occur, they should be renewed. Now that said, I have not tried any chemicals, so let's see if people have and what they say.

Good luck.
Click to expand...

I agree 100%.

Those chemicals in auto stores don't clean the cats themselves. They probably help with combustion to "CLEAN" the exhaust before it get to the cats.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Nov 12, 2005
#6
  • Nov 12, 2005
  • #6
Paul is correct. You shouldn't put ANY chemicals on the cats. You stand more of a chance of damaging the rather fragile catalysts that are on the ceramic matrix. If they won't do their job, it's replacement time.
 
A

Allforspeed

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Oct 25, 2004
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Nov 12, 2005
#7
  • Nov 12, 2005
  • #7
thanks guys, i guess just rinse it out with water and throw it on there

wish me luck with my smog adventure tomorrow!.....
 

302RollinHard

New Member
Sep 26, 2005
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Columbus, OH
Nov 12, 2005
#8
  • Nov 12, 2005
  • #8
All that you should do to your cats is put them on and make sure that they are good and hot before you smog. I wouldn't even flush them out because I don't think that it will do anything. Most important is to make sure that your car is running right and that it is hot before you go. You should be alright.
 
A

Allforspeed

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Oct 25, 2004
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Nov 12, 2005
#9
  • Nov 12, 2005
  • #9
probably be fine but the previous owner put a E-303 cam i think in it with stock intake and stock heads, super stupid thing to do and it makes the car slower while also making it tricky to pass smog, sweeeet.... i think i'll be fine though i passed on this H pipe before

thanks veryone
 

95COBRA241

New Member
Sep 3, 2005
339
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0
Delray Beach, FL
Nov 12, 2005
#10
  • Nov 12, 2005
  • #10
The e-cam is supposed to be emissions legal however with the right tune almost any cam combo can be made to pass emissions with cats. Besides the cats being warmed up prior to your sniff test, the car should be in good tune. If the A/F is not right, it will cause you to fail even with a stock cam and heads.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Nov 12, 2005
#11
  • Nov 12, 2005
  • #11
Don't rinse it out with WATER!!!! Don't rinse it with anything -- Just put the H-pipe back on.....
 
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