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Discussion Starter #1
My onboard comp keeps giving me the Warning Message "Check Gas Cap Now"...typically what will happen is i will start my car..get about a mile down the road and all of a sudden my fuel needle starts dropping like crazy...i will lose 20 miles in the matter of 10 seconds. and i notice that it doesnt feel like my engine isnt reacting to the accelorator. at that point i pull over the car shut the engine off and release the gas cap to a release of pressure i could only compare to pulling off a radiator cap or an oil cap after driving for a long period of time...once i screw the cap back on the issue is fixed.

I dont think this is a gas cap issue..im thinking its more fuel pump related or fuel filter..
any ideas?
 

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My onboard comp keeps giving me the Warning Message "Check Gas Cap Now"...typically what will happen is i will start my car..get about a mile down the road and all of a sudden my fuel needle starts dropping like crazy...i will lose 20 miles in the matter of 10 seconds. and i notice that it doesnt feel like my engine isnt reacting to the accelorator. at that point i pull over the car shut the engine off and release the gas cap to a release of pressure i could only compare to pulling off a radiator cap or an oil cap after driving for a long period of time...once i screw the cap back on the issue is fixed.

I dont think this is a gas cap issue..im thinking its more fuel pump related or fuel filter..
any ideas?
It's an evap emissions system issue. "Check Gas Cap" means one thing & one thing only: the evap emissions system has failed the large leak test. Is your check engine lamp ON? Even if not, you should read it for any pending DTC's. You may have an evap emission leak in the fuel filler neck, the vent valve, a hose, etc. It usually requires a smoke test of the evap emission system to find the leak. It is usually not an emergency situation but you should look into it. And with your weird symptoms, the sooner the better. You won't pass an emissions test & there is the little matter of your $4/gal gas evaporating into the atmosphere.

One thing you can do is crawl under the car & take a look at the evap canister. It is not uncommon on these cars for it to get crushed by careless lifting on a hoist. If so, it would have popped the gas cap message soon after the hoist lift. You would see physical damage if that were the case. That would open up a large leak in the system. Evap can is 3.


 

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Discussion Starter #5
ok thanks for the help guys...i do worry its fuel pump related because of the drop in gas..also there are times where i push the accelerator down and it just feels like somethings clogged between the tank and getting the fuel to where it needs to go....also from another post it has me thinking it could be the cat causing the acceleration issue...i have a really bad heat problem under the car. I cant even stand next to the car in the winter because my shins are on fire with the ammount of heat that comes from my under carriage....could this be cat related?
 

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Check your gas cap

I have the exact same problem. I've taken it to the dealership and they just give me a new gas cap and refuse to test it any further. Sucks now because my check engine light comes on now with the check gas cap and I've noticed when on the freeway and I try to pass someone...seems to be sluggish and my warranty is now expired. 2 months expired. Wonder if I can go back and make them fix this problem. :(
 

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ok thanks for the help guys...i do worry its fuel pump related because of the drop in gas..also there are times where i push the accelerator down and it just feels like somethings clogged between the tank and getting the fuel to where it needs to go....also from another post it has me thinking it could be the cat causing the acceleration issue...i have a really bad heat problem under the car. I cant even stand next to the car in the winter because my shins are on fire with the ammount of heat that comes from my under carriage....could this be cat related?
Did you even read my post? I am not pulling my answers out of my butt. But by all means, feel free to throw all the parts you want at the problem. Eventually you'll replace the right one. It's your money.
 

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Discussion Starter #8
yes i read your post and i will surely take that into account for my gas cap problems, however the sluggish response from my accelerator and the "cylinder 3 misfire" readout from my check engine light...do not appear to be related to an evap issue...that is why i worry the latter half of my complaints are fuel pump related....
 

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Check Gas cap

I've got an 06 G6 GT with almost 120k miles on it. "Check Gas Cap" started a few months ago. I finally bought a new gas cap at Auto Zone and I thought I fixed the problem. My husband started driving it and said he never saw the warning again. But of course, the first time I drive it after the new gas cap, it dings and shows "Check Gas Cap" again... and... drum roll... Then I got the dreaded check engine light! Checked the code on that at home and it was PO455.
I took it in. It's been at AAMCO since Monday. They said it was throwing 4 codes. They are charging me $400 to run diagnostics on all four codes. It's now Friday and I still don't know what is wrong with it. I think my AAMCO is under new management and they are probably screwing me. The only reason I took it there is because I had a similar issue with a different automobile about two months ago, and they had awesome service and went out of their way to help me and to not screw me. So, I am probably very, very screwed right now.
I have done every scheduled maintenance on this car (and then some). Besides putting four or five sets of rotors and 6-8 sets of brakes on this thing, and constantly having to get it aligned and balanced, I really haven't had any "system" trouble with it. It got new spark plugs and lots of new goodies, and it recently passed its smog check.
So... This sucks, and it's quite surprising, since it got a clean bill of health on it only a few months ago.
Anyway, I'll let you all know what they find.
 
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