huh. I was curious so I double checked.. yeah, acdelco.
maybe it's different somehow? no clue.
What did you do to your NNBS GMT900 Tahoe/Yukon Today?
- Thread starter phattyford
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huh. I was curious so I double checked.. yeah, acdelco.
maybe it's different somehow? no clue.
gooffeyguy
Tom
Are there certain years that are more likely to have the charcoal cannister leaking pellets problem, or the entire GMT900 generation?
honestly no clue.. the threads I've seen are older trucks but it's probably mileage based, so older having more miles makes sense. I've always seen the theory some people over fill their tank more than others causing issues. it does seem like the manufacture changed at some point. my oem says expert on it, the replacement says stant. stant might have just bought them out thou.. I think they did that with a lot of thermostats. still can find Motorrad on them in a stant box somethings.
most just consider it maintance item around 130 or so. something easy ish to change but once failed it becomes a nightmare.
I have only seen it reported on the gmt800's but it's the same freaking design.........
Every time I am at a gas station, I see people clicking the filler handle over and over making sure that fuel is all the way at the top of the filler neck.
Anyone that has taken a look at the evap system knows the vapor return is up at the top of the filler neck and if you get fuel flowing back into the vapor line, it will contaminate your canister and your valve.
When I fill up, after the first click I am done.
On occasion, this means that I am slightly below completely full but that doesn't bother me as much as needing to shotgun my entire evap system.
A few years ago I did the evap valve, vent and lines on my sister's 2009 Silverado.
Canister was fine and has been fine thus far.
The new kit recommended mounting the vent up higher by the filler neck to move it from the lower position along the frame where it is exposed to more road grime and to prevent a siphon action should someone overfill the tank.
I will admit that I didn't know any better years ago and when on road trips we'd always do a few extra clicks. but know better now.
we had a Ford at work that never really got used, just sat parked to side, turns out the fuelers would come by every week and top off the tank. when it did get used they would be driving down the highway and it randomly shut off. after we spent some time trying to figure it out, finally noticed any time the valve would open it would go pig rich and die. took the canister off and it was completely full of fuel. ended up having to put a locking gas cap on it and take it off site when it needs fuel.
such a hassle but it never lost it charcoal and it was probably like that for years before it actually killed the engine
blackelky
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Weird hopefully they sent me a good one. I too am just replacing it before it goes bad.
kbuskill
***CAUTION*** I do my own stunts!
Looks like the Torque Pro app.
Charlie207
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Low Buck Truck cam arrived. Basically a Truck Norris clone.
mikeyss
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Not today, but last weekend I installed my Mechman 250 amp alternator and upgraded the wiring. More pics are on my under construction page, but here's a few:
looks right, but where is that ground wire from the alternator bracket going? I ran mine from there to the frame on drivers side.
I assume you ran it to the firewall?
mikeyss
Full Access Member
It runs through the RVC sensor then to the negative side. It's how the instructions told me to do it. I still kind of find it odd..
I have both battery negatives connected together for the sensor, but the alternator mounting bracket ground that I added just goes to the frame.
I don't think that one has to go thru the sensor, pretty sure the sensor is just for the battery ground, otherwise all grounds would go thru it.
did mechman change the instructions?
mikeyss
Full Access Member
I will post a picture of the instructions I have either tomorrow or this weekend so we can compare notes
The one thing I remember my instructions saying was to not add a ground to frame. I will definitely snap pics of my instructions for you to see.
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mikeyss
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mikez71
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Those instructions make logical sense to me, though the factory dual battery setups I have seen in the PPV/SSV section are not wire as such.
The second battery ground goes straight to alternator bracket. I suspect GM didn't put too much thought/care into it.
Regarding the RVC sensor, I don't believe it to be used for anything other than keeping track of amps so it can maintain the battery down to minimal safe levels / minimal charge cycles? Or is there something else it helps with?
The second battery ground goes straight to alternator bracket. I suspect GM didn't put too much thought/care into it.
Regarding the RVC sensor, I don't believe it to be used for anything other than keeping track of amps so it can maintain the battery down to minimal safe levels / minimal charge cycles? Or is there something else it helps with?
my alternator is wired to the main battery positive
then the battery posiitive splits to small fuse bracket/link to -vehicle main fuse box, etc
the battery positive also goes to the starter and then from the starter to the 2nd battery positive
main battery negative goes thru the rvc sensor to passenger side head and the litle 8 gauge goes to the passenger side frame
2nd battery negative goes to the main battery negative.
alternator bracket I added a ground to frame
everything works fine. been that way for 4 years now
previous to that I had the 2nd battery grounded to alternator bracket and frame like the early gmt800's only the main battery was connected to the rvc sensor
and both batterys had positive to alternator and starter.
but had a bad battery and while trying to figure out the issue just wired it as above and 2 new battery's and no problems since
Adding additional grounds is never a bad thing.
Extra ground leads have solved many a strange issue in previous vehicles I have owned.
One had a weak grounding point under the battery and the temp gauge would freak out every once in awhile.
Also, the lights would dim with low idle, headlights on, wipers on and defrost blowing going.
All that went away with additional grounding.
On my 2002 Nissan Altima SE, I added a grounding kit not long after I bought it new and it has the original alternator 250k miles later.
Some owners of 3rd gen Altimas had weird things happen like eating MAF sensors or alternators but I have had no such issues.
Only thing I have replaced on that car is, starter at about 200k, fuel rail pressure regulator, one fuel injector and the AC compressor this past summer.
I plan on adding a grounding kit to the Denali in the near future.
Extra ground leads have solved many a strange issue in previous vehicles I have owned.
One had a weak grounding point under the battery and the temp gauge would freak out every once in awhile.
Also, the lights would dim with low idle, headlights on, wipers on and defrost blowing going.
All that went away with additional grounding.
On my 2002 Nissan Altima SE, I added a grounding kit not long after I bought it new and it has the original alternator 250k miles later.
Some owners of 3rd gen Altimas had weird things happen like eating MAF sensors or alternators but I have had no such issues.
Only thing I have replaced on that car is, starter at about 200k, fuel rail pressure regulator, one fuel injector and the AC compressor this past summer.
I plan on adding a grounding kit to the Denali in the near future.
