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Catalytic Convertors

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On 12/21/2022 at 4:31 AM, Victor Brown said:

Just curious is the catalytic converter on a 2002 Silverado 1500 Ls compatible with a 2017 Chevy Silverado 1500 LT

A cat only plugs from misfires. If you have that all sorted out, then change cat. There are expert welders that can change your cat, weld it in place. it's often done, you just have to locate good muffler fabricators

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On 12/23/2022 at 7:53 AM, Victor Brown said:

I thought this was a place we bounce ideas off of each other y am I being questioned like I don't know what I'm talking about instead of telling me where you think I'm wrong which I'm not try helping me out it has everything to do with the cat for example what steps would you take if you had a deep scan of your vehicle done and you came up with one code so you think you have the problem pinpointed well after repairing all areas that have to do with that code your problem still exists what would you all do that's all I'm here for advice not who's wrong or who's right



Well.  Plenty of us here are more than willing to help.  It gets a bit harder when those that ask for help don't provide enough detail or the right details.  


I know that I asked if you have the actual codes and could post them here as the codes are a diagnostic aid that can help others and myself on here try to steer you in the right direction.


Instead, you seem to be getting defensive and are now quoting a random googled source.  


A bad catalyst will NOT cause a flashing check engine light.  A flashing check engine light indicates a failure or issue that can lead to damaged catalysts, not flashing light = bad catalyst.  If you keep driving it flashing?  Yea, you can get to that point.  If you don't have a P0420 code or P0430 code, its 99.9% not a catalyst issue.


So.  What were the exact codes you have?  Not just "misfire on 3 and 5", what were the code numbers?  Was it more than just those two?  Do you have any knocking, tapping or ticking noises?  Bad camshafts occur in these engines sometimes and bad lobes can cause misfires.  3 and 5 aren't AFM cylinders however there has been valve spring failures on these engines.  


The 14-19 trucks are known to have fuel injectors fail.  Bad injectors can for sure cause an active misfire.  Have you had an injector balance test run?    

Edited by newdude
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  • 2 weeks later...

I'm with Newdude.


Just because you changed the coils and wires doesn't mean you fixed all possible missfire problems.  If the cat is bad it's because of a missfire.  The cat is down stream of the  engine and probable not cause of a missfire.  I will make it run rough but not cause a specifice miss fire in 3 and 5 only.


You need to go get a cheap scanner and read your codes again.


It could be an injector which is common.  And pray it's not a lifter.

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If you converters were failing or have failed, your secondary O2 sensors would detect this and throw the appropriate DTC code. A misfire is not going to be caused by a bad converter and especially not only on 2 cylinders.


As already stated, you need to look at spark plug, ignition coil, plug wires, injector etc. 

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I don't think we are going to find out anything further on this subject. It appears that @Victor Brownmay have taken taken his ball and gone home. He hasn't been back since Dec 24th. Maybe he will prove me wrong???

Edited by mikeyk101
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