What did you do to your NNBS GMT900 Tahoe/Yukon Today?

[Doubeleive]

Perhaps you have gained weight in your right foot.

maybe, but even when I purposely drive the speed limit it doesn't seem to change, I guess I can try and granny it for a bit and see what happens

 

[Doubeleive]

I know it’s a dumb question but have you checked the dashboard estimated mpg with the manual method of fill tank, drive, refill tank and do the math?

no, but I will next time I fill it up

 

[BG1988]

well from what I have read the cat temps seem to be pretty normal, on the freeway they ran in the 1500's both of them dead even same temp no matter what it was, fuel trims seem to be normal, all 4 02 sensors seem to be normal also, so i'm stumped.

1500F degrees? your running rich
leaking fuel injector..


815C is passed the limit where damage can occur you can bet it will need replacement very soon..


it should be running 525C(Minimum operating temperature and meeting said parameters etc etc.)


other wise it will trigger P0420

650C is typical unless your towing 3.5k rpm and going up hills etc..then it could be higher


Yes both temps should be identical

 

[Doubeleive]

according to the interwebz 1200-1600 is normal under a load and there should not be any melting unless 2000 deg or more is reached.
I am thinking of getting a backpressure test anyway just to be sure, I don't really feel like getting under there myself in 100deg weather, I would imagine the muffler shop could do it on the rack for a reasonable price.

 

[BG1988]

according to the interwebz 1200-1600 is normal under a load and there should not be any melting unless 2000 deg or more is reached.
I am thinking of getting a backpressure test anyway just to be sure, I don't really feel like getting under there myself in 100deg weather, I would imagine the muffler shop could do it on the rack for a reasonable price.

according to the manufacture it's a 3 way catalytic converter..


https://www.open.edu/openlearn/scie...way-catalytic-converter/content-section-1.5.2


i'm going out on a long trip about hour and 1/2 i'll let you know the readings that should be about a baseline

 

[kbuskill]

according to the interwebz 1200-1600 is normal under a load and there should not be any melting unless 2000 deg or more is reached.
I am thinking of getting a backpressure test anyway just to be sure, I don't really feel like getting under there myself in 100deg weather, I would imagine the muffler shop could do it on the rack for a reasonable price.

Mine normally run in the 13-1400° range while cruising around in town.... around 7-800° after idling for a while... if my memory serves me.

I guess it all depends on how hard you drive/accelerate... I'm not to ******* my old gal.

 

[BG1988]

2000F is the melting point

https://www.walkerexhaust.com/support/tech-tips/common-catalytic-converter-q-and-a.html


https://www.magnaflow.com/blogs/magnaflow/magnaflow-on-how-cats-work-part-1


1200°F is the max operating temperature under heavy load

i would trust what a cat manufacture says rather then other random stuff on the internet
they all claim over 1200F could cause premature failure

 

[CHOO CHOO]

Just cut the cats out like I did and you don't have to worry about it anymore [emoji1745]

 

[wendal]

Finally got caught up on this thread, so I can add my latest. Oil change and under hood lighting. Shout out to @kbuskill for the idea. I've had the parts for damned near a year. Pics here:

https://www.tahoeyukonforum.com/thr...-thread-retroactive.99470/page-7#post-1372562

 

[Doubeleive]

Just cut the cats out like I did and you don't have to worry about it anymore [emoji1745]

I wish, o'l Gavin Newsom would have a baby cow if I did though