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Cherry red cat

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  #1  
Old 02-07-2012, 06:15 PM
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Default Cherry red cat

Just noticed that my cat was cherry red 2 seconds ago. when the code was pulled it said probable cause was o2 sensor, Maf, or low fuel pressure. There is a new after market fuel reg. as well as brand new MAF. Could it simply be the O2 sensor? If not im pretty sure I need a new cat but deff do not have the money. any thoughts about either deleting everything from cat back or use a straight pipe where the cat would have been? please help, very low on money and need all the help i can get.
 
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Old 02-07-2012, 06:30 PM
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BTW its a 4cyl 1.8T
 
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Old 02-07-2012, 06:46 PM
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Cats don't usually glow because they are bad. Something is causing a bad fuel mixture. Check the fuel pressure regulator. Pull the vacuum hose off & make sure you don't have fuel coming out.
If you have the capability check fuel trim values & see what the ecm is tryng to do (lean out or richen up).
It is possible the cat could be clogged but again it is usually caused by another problem.
 
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Old 02-07-2012, 06:46 PM
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Aftermarket fuel pressure regulator? Is it operating at a different pressure than your tune is designed for? If you're running a stock or Stage 1-chipped ECU then your fuel pressure should be 4bar. If your fuel pressure is something else then that could be a problem.

An old primary (pre-cat) O2 sensor will cause a richer mixture, so that could be another possibility if the previously-mentioned isn't true.
 
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Old 02-07-2012, 06:53 PM
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this was recently bought and to my knowledge it was tuned by APR I beleive. I can run at 20 lbs of boost. eventhough i get a lot of hesitation when im wot. so could all of this be due to a simple $80 part?
 
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Old 02-07-2012, 06:56 PM
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also is it safe to drive 14 miles a day w/ out making my situation any worse?
 
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Old 02-07-2012, 07:07 PM
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Originally Posted by Audi_Marine4life
also is it safe to drive 14 miles a day w/ out making my situation any worse?
Not a good idea with a glowing cat!
 
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Old 02-07-2012, 07:18 PM
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so any advice on what to do. please dont just say take it to the shop.
 
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Old 02-07-2012, 07:37 PM
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Let the chip regulate your fuel like it should be...
 
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Old 02-07-2012, 07:45 PM
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Let the chip regulate your fuel like it should be...
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ok so how does that help? I havent changed anything. did u read the whole post?
 


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