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

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Doubeleive

Wes
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by all 3 you mean the valve under the hood, the charcoal canister and the vent valve in the back right?
but I had no issues before changing the canister. no codes or anything. how would changing the canister effect the under hood valve? I could see if when I first stated it had a leak. at that point narrowing down which one of the 3 had a leak would be more hassle than just replacing all 3 at once.

at this point I've changed 2 of the 3. should I just throw a new valve under the hood for sport? again, I wasn't fixing a code to begin with everything worked.
what prompted you to change the canister?
if that was all you did then the canister is possibly no good or went bad.
I tried to save a few bucks and initially bought aftermarket, stupid thing lasted 3 months, threw it in the garbage and bought oem, no problems since
 

j91z28d1

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just reading this site and the threads about pellets in the evap system. grabbed a oem one off rock auto and put it on. figured worth the money to avoid the hassle later. since these trucks all seem to follow the same failure trends.

I still have the old one. I think I'll swap it in and see if I just got a bad one. looks like a oem one, it is my luck thou haha. I'll make sure I didn't mess up an o ring too. the 2 small hoses came off easy. the big one I fought with a bit, so that's why I replaced the rear vent valve with oem too. thinking I probably cracked something.. blah.


on a side note. anyone know off the top of their head if the oem spare tire has a pressure sensor valve stem in it? I'm about to mount up a tire on a new spare rim and got to wondering. can't find anything on Google besides some cars do and some don't. if not, how does the truck react when you put a spare on it and the tire sensor reads the flat still in the back of the truck?

I know the c6's lose their mind without pressure sensor readings. go into limp mode and won't drive but like 40mph or something. guys take the tire sensors, put them in a pvc pipe capped off. fill it with 35psi and throw it in the back of the car as a work around.
 

solli5pack

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just reading this site and the threads about pellets in the evap system. grabbed a oem one off rock auto and put it on. figured worth the money to avoid the hassle later. since these trucks all seem to follow the same failure trends.

I still have the old one. I think I'll swap it in and see if I just got a bad one. looks like a oem one, it is my luck thou haha. I'll make sure I didn't mess up an o ring too. the 2 small hoses came off easy. the big one I fought with a bit, so that's why I replaced the rear vent valve with oem too. thinking I probably cracked something.. blah.


on a side note. anyone know off the top of their head if the oem spare tire has a pressure sensor valve stem in it? I'm about to mount up a tire on a new spare rim and got to wondering. can't find anything on Google besides some cars do and some don't. if not, how does the truck react when you put a spare on it and the tire sensor reads the flat still in the back of the truck?

I know the c6's lose their mind without pressure sensor readings. go into limp mode and won't drive but like 40mph or something. guys take the tire sensors, put them in a pvc pipe capped off. fill it with 35psi and throw it in the back of the car as a work around.
Double check that all the pipes are clicked all the way onto the canister. Same thing happened to me and I found one of the pipes not seated properly and wasn't clicked in. I ended up getting a code for a large leak though.
 

Doubeleive

Wes
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just reading this site and the threads about pellets in the evap system. grabbed a oem one off rock auto and put it on. figured worth the money to avoid the hassle later. since these trucks all seem to follow the same failure trends.

I still have the old one. I think I'll swap it in and see if I just got a bad one. looks like a oem one, it is my luck thou haha. I'll make sure I didn't mess up an o ring too. the 2 small hoses came off easy. the big one I fought with a bit, so that's why I replaced the rear vent valve with oem too. thinking I probably cracked something.. blah.


on a side note. anyone know off the top of their head if the oem spare tire has a pressure sensor valve stem in it? I'm about to mount up a tire on a new spare rim and got to wondering. can't find anything on Google besides some cars do and some don't. if not, how does the truck react when you put a spare on it and the tire sensor reads the flat still in the back of the truck?

I know the c6's lose their mind without pressure sensor readings. go into limp mode and won't drive but like 40mph or something. guys take the tire sensors, put them in a pvc pipe capped off. fill it with 35psi and throw it in the back of the car as a work around.
no sensor in the spare and no hinderence in the drivetrain from a tpms message. (on this generation truck)
as far as your canister goes just keep in mind when you put the original back on it takes a "while" for the evap to set, could be a anywhere from 3 days to 2 weeks or longer
some scanners will show if it is ready or not if you check it from time to time, same thing happens if the battery is disconnected.
 

89Suburban

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on a side note. anyone know off the top of their head if the oem spare tire has a pressure sensor valve stem in it? I'm about to mount up a tire on a new spare rim and got to wondering. can't find anything on Google besides some cars do and some don't. if not, how does the truck react when you put a spare on it and the tire sensor reads the flat still in the back of the truck?

I know the c6's lose their mind without pressure sensor readings. go into limp mode and won't drive but like 40mph or something. guys take the tire sensors, put them in a pvc pipe capped off. fill it with 35psi and throw it in the back of the car as a work around.


I have not seen any in the spare. These trucks will no go into limp mode over a TPMS reading, just the tire light and warning message shows up.
 

j91z28d1

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Double check that all the pipes are clicked all the way onto the canister. Same thing happened to me and I found one of the pipes not seated properly and wasn't clicked in. I ended up getting a code for a large leak though.


yeah, I pushed on them then I did the rear valve, but I'll check when I swap it. mine is called a small leak so who knows. you'd think I could swap it without breaking something. but maybe not haha.
 

j91z28d1

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no sensor in the spare and no hinderence in the drivetrain from a tpms message. (on this generation truck)
as far as your canister goes just keep in mind when you put the original back on it takes a "while" for the evap to set, could be a anywhere from 3 days to 2 weeks or longer
some scanners will show if it is ready or not if you check it from time to time, same thing happens if the battery is disconnected.


yeah, I don't know if it's the cooler Temps right now or not, but it took almost a month to run the test this time. from what I read it measures the air pressure from the heating and cooling of the fuel in the tank. all kinds of crazy parameters it has to hit to run the test. but my easy to use app I check every few days while driving (I'm the Bata tester for the lithium battery swap company, so I get them data pretty often as everyone else has them in a prius) shows if the test is run or not. once it finally changed status the light was on haha.
 

Doubeleive

Wes
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yeah, I pushed on them then I did the rear valve, but I'll check when I swap it. mine is called a small leak so who knows. you'd think I could swap it without breaking something. but maybe not haha.
maybe since it is usually dusty & dirty under some grit managed to get in, try some compressed canned air to blow it all out.
 

j91z28d1

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I have not seen any in the spare. These trucks will no go into limp mode over a TPMS reading, just the tire light and warning message shows up.


thanks..

out of curiosity I threw the bare rim on the balancer and it showed 1oz needed exactly at the valve stem hole. so it lead me to the valve stem is only 0.25oz. I wondered if they went as far as to cast it with a sensor weight in mind.

but, cool. I'll mount this thing up.
 

Sparksalot

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just reading this site and the threads about pellets in the evap system. grabbed a oem one off rock auto and put it on. figured worth the money to avoid the hassle later. since these trucks all seem to follow the same failure trends.

I still have the old one. I think I'll swap it in and see if I just got a bad one. looks like a oem one, it is my luck thou haha. I'll make sure I didn't mess up an o ring too. the 2 small hoses came off easy. the big one I fought with a bit, so that's why I replaced the rear vent valve with oem too. thinking I probably cracked something.. blah.


on a side note. anyone know off the top of their head if the oem spare tire has a pressure sensor valve stem in it? I'm about to mount up a tire on a new spare rim and got to wondering. can't find anything on Google besides some cars do and some don't. if not, how does the truck react when you put a spare on it and the tire sensor reads the flat still in the back of the truck?

I know the c6's lose their mind without pressure sensor readings. go into limp mode and won't drive but like 40mph or something. guys take the tire sensors, put them in a pvc pipe capped off. fill it with 35psi and throw it in the back of the car as a work around.
I have 5 tires with sensors on both of mine. For the GMT900 it doesn't care which 4 are programmed. One of those could be the spare. If you have a flat it's going to just set a nag on the DIC.
 

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