Exhaust and catalytic conv.

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Knightro
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Exhaust and catalytic conv.

Postby Knightro » Sat Jan 25, 2014 6:56 am

The check engine soon light just came on in my '06 pathfinder. Was at tire store getting some work done and they checked the code. Came up with a bad catalytic converter. Sucks since I only have 82,300 miles on the vehicle.

My question is for those who have replaced their exhaust systems, how did you address the converters? Are the old converters still part of the system or are they removed? I'm concerned with passing state vehicle inspection (NJ). Also if the exhaust system is replaced and exhaust flow is increased are there any adjustments needed to the engine?

Any suggestions?


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smj999smj
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Postby smj999smj » Sat Jan 25, 2014 11:25 pm

If you remove the catalytic converters, you will constantly trip the P0420/P0430 DTC's (unless you use some kind of O2 sensor simulators and trick the ECM) and you will fail NJ state inspection. It is also Federally illegal to remove them. As far as making adjustments, no, the decrease in backpressure will not require any adjustments (since engine management is computer controlled, there's nothing to adjust, anyway).

NVRDONE
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Postby NVRDONE » Mon Jan 27, 2014 8:08 pm

Front or rear cats ? The front cats are monitored by the ECM. The rears are not monitored. I've heard of replacement pipes or some owners just gut the second cats and put them back in

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smj999smj
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Postby smj999smj » Mon Jan 27, 2014 8:47 pm

Since he said it set a code due to bad converters, I'm assuming he is referring to the front converters.

Knightro
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Postby Knightro » Tue Jan 28, 2014 1:46 pm

Thanks for the replies. I think they said it was bank 2 cat. From what the dealer tells me there are 2 catalytic converters on the vehicle. Unfortunately the tire shop cleared the code so the dealer wasn't able to see it. I'm waiting for the light to come back on. About 100 miles so far. Normally I'd crawl under the car and look for myself but it's freezing here and my truck is caked with snow and road muck.

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oreogaborio
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Postby oreogaborio » Tue Jan 28, 2014 4:43 pm

I've got the same issue. Planning on replacing them myself before inspection in a few months. I've been able to find both front cats for about 4-600 dollars shipped online.

Looks like a fairly straight forward install... hoping I'll just need plenty of PB blaster and some elbow grease.

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disallow
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Postby disallow » Wed Jan 29, 2014 7:23 am

in my experience, impact tools are a must for work on exhaust systems, especially if they are a few years old.

NVRDONE
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Postby NVRDONE » Wed Jan 29, 2014 8:03 pm

From my experience there are four cats. Two primary at the exhaust manifolds and two secondary be hind the primary ones.
To replace the primary ones generally plan on some broken bolts and studs
The heat shield bolts on the primary cats are the biggest problem. But you don't need the shields.
Use lots of p b blaster and lots of patientce

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smj999smj
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Postby smj999smj » Thu Jan 30, 2014 6:10 am

Yes, there are 4 converters. Only the front converters are monitored by the O2 sensors. Bank 2 is the left, or driver's side (US).


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