Issue at a gas station

[homesick]

Do the Gmt800 trucks use the same style charcoal canister as the gmt900 trucks? My 2001 has the original charcoal canister and evap line/system and have never had any kind of problems like this at ~260k miles.

Also has original coil packs, exhaust, cats, muffler

I've read that that generation [2000-2006] is above average in quality. My '01 has sure been a good one.

joe

 

[petethepug]

You’re right. The NBS / 01-06 trucks use a similar carbon canister but a different part number. I’ve never seen issues with them like the NNBS / 07-14 have had.

 

[Trilla_one]

My 2007 with 239k miles has a similar issue that started a year ago. I still haven't been able to figure it out. It has an extra long crank sometimes and sometimes it only starts on the 2nd try with difficulty like yours does. Mine has no correlation with gas stations though.

I do have a large evap leak code that I have not been able to pin point, and I smell old gas around the rear of the truck 95% of the time. The smell is usually stronger while i'm filling up(maybe it's because i'm standing back there). So far I have replaced the Fuel pump, Charcoal cannister, Vent valve, Purge valve, Gas cap(at least 3 times), and even 02 sensors. Problem still exists

I have however noticed that the starting issue only happens if I am below 1/4 tank so I have been getting by keeping it above. The only other thing I can think of trying next is to have the dealer do a smoke test. Good luck resolving your issue.

Fix update:

Had a smoke test done a month later and a leak was found coming from the Purge valve's rear main hose. It looked to be about 2 feet long and ran from behind the valve down the firewall.

It's been a few months and no more starting issue, EVAP codes, or gas smells. Hope this helps someone.

 

[petethepug]

Replace your carbon canister and take a win. If it fails before you replace it, you’ll be replacing the remainder of the evap system components, fuel pump, level sensor and the labor to pull the tank and swab all the pellets out.

Not wishing it on you, just hoping to save you from a needless, known expensive scenario.

 

[petethepug]

@tabatharuff did you ever get this figured out?

So we have a 2007 Chevy Tahoe and it starts & runs great except when we go to this one particular gas station. After fueling up when we go to start it it turns & cranks but doesn't start right away, & then we do it again & it starts with a little difficulty. Every other place including other gas stations it starts fine can anyone tell me why this is happening. It doesn't what time of day but it is literally every time we go to this gas station...

 

[Fless]

@tabatharuff did you ever get this figured out?

Hit and run. One hit wonder.

 

[Scrappycrow]

Replace your carbon canister and take a win. If it fails before you replace it, you’ll be replacing the remainder of the evap system components, fuel pump, level sensor and the labor to pull the tank and swab all the pellets out.

Is there a particular line coming off the canister that's the culprit, or does it fail internally and spread the pellets into all/multiple lines? If it's the former, installing a 100-micron fuel "pre filter" might be good insurance.

 

[kbuskill]

Is there a particular line coming off the canister that's the culprit, or does it fail internally and spread the pellets into all/multiple lines? If it's the former, installing a 100-micron fuel "pre filter" might be good insurance.

The line coming off the charcoal canister that leads to the EVAP purge solenoid is the one that gets the pellets sucked up into it due to the engine vacuum when the purge valve opens.

When mine puked pellets they ended up all the way up in the purge solenoid and they would actually cause the valve to stay open. I ended up disconnecting the line at the canister and at the purge valve and blowing compressed air from the purge valve/engine back toward the canister and a bunch of pellets came out of the line. This was after replacing the purge valve a couple times thinking I just got a bad one at the local parts house. Since changing the canister and clearing the line I haven't had any issues.

 

[petethepug]

My gosh, if GM had a fuel filter or filter on the evap canister I would have missed all the months of fun chasing down the problems the pellets created.

There’s no way I’m sharing all that fun with a dealer service technician, that’s my kinda good liv’n and not sharing it with anyone.

Is there a particular line coming off the canister that's the culprit, or does it fail internally and spread the pellets into all/multiple lines? If it's the former, installing a 100-micron fuel "pre filter" might be good insurance.