2015 Tahoe/Bad catalytic converter

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DixieL

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I have a 2015 Tahoe that I recently had the catalytic converter replaced with an aftermarket one. Drove 2 weeks and the engine light came back on, they reset and I drove it for a while, light came back on. Took it back in and they replaced the cat again thinking it was a bad part. Drove another 2 weeks and the light is back on. Mechanic said sometimes tahoes don’t like aftermarket cats and if I want it fixed I’ll need to pay the difference for an OEM one. Does this sound right?
 

OR VietVet

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Welcome to the forum.

I agree that with emission parts, the OE GM stuff is best but I would also want to know what the code(s) are. What was the diagnostic process? I can assure you that there is no code that comes right out and says a cat is bad. Bad readings and reactions, yes. But what caused that. The cats may start out ok but something upstream is damaging them quickly. Need to know those codes.
 

Miami-Dade

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I have a 2015 Tahoe that I recently had the catalytic converter replaced with an aftermarket one. Drove 2 weeks and the engine light came back on, they reset and I drove it for a while, light came back on. Took it back in and they replaced the cat again thinking it was a bad part. Drove another 2 weeks and the light is back on. Mechanic said sometimes tahoes don’t like aftermarket cats and if I want it fixed I’ll need to pay the difference for an OEM one. Does this sound right?
PLEASE use Only OEM products on your 2015 Tahoe from here on in. On Everything.

Welcome from Miami Beach&Queens NY.
 

Sam Harris

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FWIW, my ‘03 has ARH longtubes, with cats, and she’s never complained about them. Not really apples to apples, but as @OR VietVet stated above, the shop needs to specify what troubleshooting they performed, what codes were read, etc.. having them installed for only 2 weeks, and experiencing this issue seems pretty shady. Where were the cats obtained from? They could be improper for the vehicle.
 

swathdiver

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I had each of them for only 2 weeks, that fast?
Could be. Or something is still wrong with the engine and killing them. There is also a caveat that a new cat will often set a code within the first 50-100 miles as it breaks in.

A massive exhaust leak on that side of the engine can throw a cat code to set too.

Would be nice to view the failure records stored in the computer when the code set.
 

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