99 yukon 120K , 350 v8, p0430 fault code bank 2

[ezbtr]

02 sensor or bad cat?

 

[xjdriver]

Re: 99 yukon 120K , 350 v8, p0430 fault code bank 2

Bank 2 just means the side of the motor with the no2 cyl. Does it say sensor 1 or 2?

 

[alldodge]

Re: 99 yukon 120K , 350 v8, p0430 fault code bank 2

The catalytic converter is no longer functioning properly
An oxygen sensor is not reading correctly
There is an exhaust leak

I would check O2 first but there is no drivability issue and your fuel mileage will stay the same so maybe just let it be.

Edit: The check engine lights gives off a nice glow at night

 

[bruceb58]

Re: 99 yukon 120K , 350 v8, p0430 fault code bank 2

It could be a lot of things, unfortunately.

What is the history of this vehicle. Any modifications including a K&N filter? How many miles? Ever change any O2 sensors before?

The reason I ask about the K&N is because they can harm MAFs and is why I would never use one.

Ever use any snake oils in the fuel like Sea Foam?

My scan software allows you to look at realtime readings of the O2 sensors before and after the cat. If you can get a hold of one of those, I would suggest it before you start throwing parts at this problem.

 

[xjdriver]

Re: 99 yukon 120K , 350 v8, p0430 fault code bank 2

Just looked up the code, either you have a bad/misreading 02sensor, or a bad cat

 

[bruceb58]

Re: 99 yukon 120K , 350 v8, p0430 fault code bank 2

Just looked up the code, either you have a bad/misreading 02sensor, or a bad cat

Unfortunately, it can be other things as well. That is why you can't go by just the code.

 

[xjdriver]

Re: 99 yukon 120K , 350 v8, p0430 fault code bank 2

But.... most likely......

 

[bruceb58]

Re: 99 yukon 120K , 350 v8, p0430 fault code bank 2

But.... most likely......

That's why I would use my diagnostic scanner that shows an analog display of the in and out of the 2 O2 Sensors to make sure. Can get expensive throwing parts at a problem. For example, a dirty MAF can cause this exact problem and all you have to try is to clean it with $6 worth of MAF cleaner.

I like to try to diagnose a problem rather than the parts shotgun approach.

 

[xjdriver]

Re: 99 yukon 120K , 350 v8, p0430 fault code bank 2

But does a 99 yukon have a maf? Im ptetty sure the spider injection 350s dont but the stadard mpi ones do, not sure what year they switched.

 

[bruceb58]

Re: 99 yukon 120K , 350 v8, p0430 fault code bank 2

But does a 99 yukon have a maf? Im ptetty sure the spider injection 350s dont but the stadard mpi ones do, not sure what year they switched.

yeah, you are probably right. Been awhile since I looked at those.

 

[ezbtr]

Re: 99 yukon 120K , 350 v8, p0430 fault code bank 2

told is a bad cat, $400 to replace??? yiii!!! I need an older pre smog truck!!

 

[xjdriver]

Re: 99 yukon 120K , 350 v8, p0430 fault code bank 2

told is a bad cat, $400 to replace??? yiii!!! I need an older pre smog truck!!

Ya, or get used to the light. Or take it out

 

[ezbtr]

Re: 99 yukon 120K , 350 v8, p0430 fault code bank 2

Ya, or get used to the light. Or take it out

it won't pass CA. smog with a bad cat

 

[xjdriver]

Re: 99 yukon 120K , 350 v8, p0430 fault code bank 2

it won't pass CA. smog with a bad cat

Hmm looks like your stuck on replacing the cat, is the 400 with the oem cat or aftermarket? I would shop around some sounds a little high.

 

[alldodge]

Re: 99 yukon 120K , 350 v8, p0430 fault code bank 2

told is a bad cat, $400 to replace??? yiii!!! I need an older pre smog truck!!

Did the person telling you this guarantee it to be the Cat?

it won't pass CA. smog with a bad cat

Found 3 from 160 to 560 at summit racing which is CA compliant

http://www.summitracing.com/search/...l/50-state?SortBy=Default&SortOrder=Ascending

 

[ezbtr]

Re: 99 yukon 120K , 350 v8, p0430 fault code bank 2

Did the person telling you this guarantee it to be the Cat?



Found 3 from 160 to 560 at summit racing which is CA compliant

http://www.summitracing.com/search/...l/50-state?SortBy=Default&SortOrder=Ascending

yes

 

[ezbtr]

Re: 99 yukon 120K , 350 v8, p0430 fault code bank 2

got it back yesterday, passed fine, CAT itself was $265, curious to see how long the other original will last