Wheres the best cheapest place to get a catalytic converter. I have a 2008 GMC Envoy 5.3 V8
1GKET63M282180357
The best catalytic converter is OEM. The cheapest would be a Chinese-made knockoff, though that may not work for long if at all. Rockauto is a good place to check options and pricing.
How do you know you need a catalytic converter?
@chucktobias Because I put 02 sensor extensions on it a year ago because of p0420 and p0430. So the check engine light will turn off for the emission check. But now my catalytic converter is so clogged all my bank 1 cylinders are misfiring
P0420 and P0430 themselves do not necessarily mean bad converters, but if clogged up and strangling the engine that would certainly be a reason for replacement!
@chucktobias I think it is the converters the codes went away after the extentions. But now I think its clogged to the point of making my engine run poorly. I have misfires on all bank 1 cylinders and a p3400 code for bank 1
You can verify converter clogging with a backpressure gauge.
https://www.youtube.com/watch?v=qJTmddbOxMk
Also, please watch language, forum rules prohibit swearing. Thanks.
@chucktobias my bad didn't realize I said that sometimes I say stuff without thinking.
No problem, just making you aware of it. I'd definitely check backpressure before spending $$$ on catalytic converters to verify that's the cause of the misfire problem. Even if clogged it could be misfiring that caused converter damage rather than the other way around.
@chucktobias Yeah I looked it up and when the misfiring is happening on just one bank its mostly the catalytic converter. Plus my scan tool said on the freeze frame data the bank 1 converter was almost 1500 degrees fahrenheit..
@chucktobias high CC temp is caused by the unburned fuel coming from your engine
@imperator - Indeed. If the converter wasn't bad before the misfires started it probably is now.