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Jerry, Master Mechanic
Category: GMC
Satisfied Customers: 17218
Experience:  ASE Master, 30+ years exp. former shop owner/ manager
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I have a 2005 gmc envoy. i have error codes p0410 and p0420.

Customer Question

i have a 2005 gmc envoy . i have error codes p0410 and p0420. i cant pass emmissions what can i do . thanks
Submitted: 1 year ago.
Category: GMC
Expert:  Jerry replied 1 year ago.

Hello and welcome. My name is ***** ***** you for visiting the site, I will be happy to assist you today.


The only way to know is by doing the tests for the codes.


I can get the test instructions for the codes it and put them in a PDF file, (it is rather large) and send it to your email address for a little bit more.


You will just have to accept the additional service offer and ENTER your email address in the private section so that I can see it. I do not have access to your email address, Thanks

Customer: replied 1 year ago.
send them to ***@******.***thanks
However my main question is it possible for the secondary air injection pump to fail and then also make a p0420 cat. code as well .
thanks .
i look forward to your answer and the testing procedures .
Expert:  Jerry replied 1 year ago.

You will just have to accept the additional service offer, thanks