How to open gas tank cover on 99 oldsmobile intrigue?

Under car,usually mounted near or in front of gas tank

https://www.google.ca/url?sa=t&rct=j&q=&esrc=s&source=web&cd=7&cad=rja&uact=8&ved=0ahUKEwiWp7rZtOfKAhVBlh4KHY1RAwYQtwIINTAG&url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DQIlti3aZ22M&usg=AFQjCNEz4TLhC8cVKeIar-IctwksFPqv_g Repair Guides Components Systems Evaporative Emission Control System... https://www.google.ca/url?sa=t&rct=j&q=&esrc=s&source=web&cd=11&cad=rja&uact=8&ved=0ahUKEwjQ4dL_tOfKAhVCGx4KHaITC3w4ChAWCBowAA&url=http%3A%2F%2Fcommunity.cartalk.com%2Fdiscussion%2F2290225%2F01-olds-alero-evap-problem-getting-choked-out-by-gas-fumes&usg=AFQjCNEyLR6NegYlup_S2N6z_mGccu_DFA&bvm=bv.113370389,d.dmo

Presume you mean that you fill the tank and even with fuul tank of gas it won't start.. It's your injection system. Get it cleaned.

in the boot behind the cover on tank side there is a lock pin. works with the central locking if it gets stuck. push it back with your finger to open fuel door. some times there is a strap you can pull and it will open the tank door.

You'll need a repair book or shop manual to get the procedures.
Code 336 is for a problem with the crank sensor circuit, and 442 is for a small leak in the evap system. The leak could be the gas cap or a hose or valve between the gas tank and the vapor canister.

Get some gas...don't forget to pour it in the tank!!!

I'm not sure what it is called, but if you from underneath at the gas hose you will see a black box with a wire going to it hooked up to the gas down pipe. Mine did the same thing and thats what I had to replace. Hope this helps

your in tank fuel pump could have went out at the same time.

Fuel pump....running tank empty ruins the fuel pump

Opps! sound like the same problem I still have.
A good mechanic with a diagnostic gizzmo can tell you about 2 or sometime another troubled spot. The 2 I know of is under your hood and have your gas filter checked. The other is the filter located just inside your gas tank. Your gas tank may have to be flushed in some cases. But first check your gas front filtration and. This effects your on board computers because it trying to correct the problem.

under the drivers door with a bracket holding the filter on. Be carful some of them have clips holding fuel lines on. might have to tak tank off, but that might lead to a leaking tank,straps a hole lot of mess. Best way is to take off filter, leave off put rubber hose on fuel line and put into a fuel can turn on the key and wait to empty.hope not to much gas in tank.