Fuel Tank Not Accepting Gas
#21
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Well that was my next step after the key since that was easier lol. I think I have one that has a broken nipple for one of the lines going to it that came with my intake manifold. I guess I will try that out and see if it helps.
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yeah the flap is at the top and the gas nozzel pushes that open but when the tank builds pressure and the evap purge solenoid doesnt purge the pressure out of it into the intake it pushes the check ball shut whiich is at the bottom of the filler tube, like at the tank itself not up where u put gas in..
#29
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I have one in my custom tank for roll over purposes - ie if I roll over, no gas will spill.
#31
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I have had this problem a few times with car that sit for a while, one was a 06 Saab 97X Suv same as an Envoy, I pulled the vent line loose on the filler neck and then put some conpressed air to it, this frees up the ck ball then everthing works fine after that
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Dammit, lol I couldnt find any kinks. I really dont want to take the tank out not knowing where I am going to go with it after its out. I wish someone that had this problem and fixed it could chime in. O well, maybe I should drill a hole in the tank and route a little hose to the filler neck with a cap so that I can release any pressure when I fill the tank. Kinda like plastic gas jugs lol.
Also the little EVAP cap on the line by the fuel rail, should anything shoot out of that when I press the needle in. I don't know because it says max of one psi.
Also the little EVAP cap on the line by the fuel rail, should anything shoot out of that when I press the needle in. I don't know because it says max of one psi.
#36
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Well I tried swapping caps with a buddy to see if that might fix it as advised. It didn't. I came across this in another thread and thought it might help some people. Also I also put my ignition to ON to listen to the radio, this says that can make it difficult to fill. Ill try this next time I fill.
Also if anyone knows where to get a Service Manual let me know.
Also if anyone knows where to get a Service Manual let me know.
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Think I got this one solved for you!
I had a customer bring me his 99 camaro 3.8 V6 with the same problem, I assume it is the same tank (maybe a different pump?). I dropped the tank after exhausting all other efforts including scan tools and EFI Live diagnostics ( I do EFI Live tuning for GM's). Here is a picture of the top of the tank, the problem was the EVAP canister vent valve/solenoid (small box next to charcoal canister with red two conductor connector). The spring inside of it popped out and was lodged in the rubber line between the valve and canister. This causes the valve to automatically close when even the slightest vent flow is created, although it will allow air back into the tank (reason why the car drove fine and had no fueling problems). It is a one way valve, but without the spring it closes during fuel tank filling. it also did not show up on diagnostics because it still works properly as far as the ECM can see (opens under vacuum). Pretty tough to diagnose!!
Rather than just stuffing the spring back in I decided to replace the unit, it was 30$ at the local GM parts dealer.
I will repost later tonight with more detailed pictures of valve and dislodged spring!
Customer is excited to fill his car at the gas station as he has been using cans a few gallons at a time for months!!!!!!!!!!!!
http://www.pelamotorsports.com/forum....php?p=520#520
I had a customer bring me his 99 camaro 3.8 V6 with the same problem, I assume it is the same tank (maybe a different pump?). I dropped the tank after exhausting all other efforts including scan tools and EFI Live diagnostics ( I do EFI Live tuning for GM's). Here is a picture of the top of the tank, the problem was the EVAP canister vent valve/solenoid (small box next to charcoal canister with red two conductor connector). The spring inside of it popped out and was lodged in the rubber line between the valve and canister. This causes the valve to automatically close when even the slightest vent flow is created, although it will allow air back into the tank (reason why the car drove fine and had no fueling problems). It is a one way valve, but without the spring it closes during fuel tank filling. it also did not show up on diagnostics because it still works properly as far as the ECM can see (opens under vacuum). Pretty tough to diagnose!!
Rather than just stuffing the spring back in I decided to replace the unit, it was 30$ at the local GM parts dealer.
I will repost later tonight with more detailed pictures of valve and dislodged spring!
Customer is excited to fill his car at the gas station as he has been using cans a few gallons at a time for months!!!!!!!!!!!!
http://www.pelamotorsports.com/forum....php?p=520#520
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I have updated the original posting with more pics, but this car has another gremlin that I have never seen before.
The ignition timing gets mysteriously advanced for no reason once the engine warms up. It was running great and then as I was driving it the timing jumped like 12 deg advanced and stayed (I actually watched it happen on the EFILive dashboard). Then it starts running like crap and missing and pinging as the knock retard shots up to like 15 deg!!!!! He mentioned it to me when he gave me the car ( I drove it when it was already warmand noticed the occasional missfire) but I just thought it was a tired V6, it actually had some good power when it was cold after the vent solenoid repair.
I will post in the appropriate forum!
The ignition timing gets mysteriously advanced for no reason once the engine warms up. It was running great and then as I was driving it the timing jumped like 12 deg advanced and stayed (I actually watched it happen on the EFILive dashboard). Then it starts running like crap and missing and pinging as the knock retard shots up to like 15 deg!!!!! He mentioned it to me when he gave me the car ( I drove it when it was already warmand noticed the occasional missfire) but I just thought it was a tired V6, it actually had some good power when it was cold after the vent solenoid repair.
I will post in the appropriate forum!
#40
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Heres an update, the last four times I fueled up I didn't leave the ignition on and the radio playing like I normally did. All four times the car fueled up fine, so I am hoping this fix wont stop when it gets warm. I will update again if it starts acting up again.