2000 CADILLAC SLS CATALTIC CONVERTER

  • Tiny
  • thunder
  • 2000 Cadillac SLS

Engine Performance problem
2000 Cadillac SLS V8 Front Wheel Drive Automatic 121000 miles

I'm getting a "P0420 Catalyst System Efficiency Below Threshold (Bank 1)" code. How many converter does my caddy have? Where is "bank 1"?

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Tuesday, September 14th, 2010 AT 7:34 AM

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  • Tiny
  • factoryjack
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Your SLS only has one converter, and I believe that's why it issues a bank 1 designation. Bank one is the bank of cylinders that includes cylinder #1, which on your vehicle is the rear bank. A catalyst efficiency code with no other symptoms, is corrected with catalyst replacement. I am not certain of the assignment of oxygen sensors for sure, but I believe you have a Bank 1 Sensor 1, a Bank 2 Sensor 1, and a Bank 1 Sensor 2. It is the pre-cat sensors(B1s1/B2s1) versus the post- cat sensor(B1s2) that determine whether or not the catalyst is functioning.

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Tuesday, September 14th, 2010 AT 11:52 PM
  • Tiny
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Can I replace it with a universal cat? Aftermarket is approx. $550 and OE is approx. $1800 and thats not including labor! (Quote from cadillac dealer)

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Wednesday, September 15th, 2010 AT 7:18 AM
  • Tiny
  • factoryjack
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You can replace with a universal one to minimize cost. The reason an aftermarket cat is more inexpensive, is the quality. Where you get 10 years and next to 100k on O.E, you may only see a few years of service on an aftermarket. In my opinion, the cost difference is a result of how much of the precious metals are used in manufacture.

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Wednesday, September 15th, 2010 AT 10:09 AM
  • Tiny
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Thanks for your help gstacey! I just want it to last one more year (one more inspection) before I give it to my daugther (she's not a road warrior like I am ;)) I have my eye on the caddy coupe next year.

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Wednesday, September 15th, 2010 AT 10:41 AM
  • Tiny
  • factoryjack
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You must be talking about the 2011 CTS coupe. We just started seeing them arrive about a month ago.

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Thursday, September 16th, 2010 AT 10:43 PM
  • Tiny
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Yea. They have them at our cadilac dealer now. I want to wait a year so they can get the bugs out and the 2011 price will come down to make room for the 2012's.

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Friday, September 17th, 2010 AT 6:55 AM
  • Tiny
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Saturday I had the Cat Conveter installed. $440 for the Cat & $140 for labor at Mineke. They even took me home and picked me up after installation. Great service.

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Wednesday, September 22nd, 2010 AT 12:46 PM
  • Tiny
  • factoryjack
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Winner-winner chicken dinner!

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Wednesday, September 29th, 2010 AT 11:21 PM

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