Thread: 99 Grand Prix 3.8 N/A won't take gas

Let me start by saying...my brother in law swears there is no way it could be full of gas. The gas gauge is pinned at full, but he says it doesn't work correctly. By all looks and appearances, it is just full of gas.

So far I have:

-completely disconnected the Evap Charcoal canister

-blown air through the hose connecting the purge solenoid to the throttle body

-blown air through the hose connecting the purge solenoid to the charcoal canister

-blown air through the hose connecting the charcoal canister to the tank

-removed the gas filler neck and blown air through the metal vent tube attached to it, and also blew air through the plastic tube which connects to the metal vent tube attached to the filler neck.

-I pushed a 4' metal spring down the filler neck to check for anything blocking the filler tube


So far to no avail, if you go to fill it the gas just pours out the filler neck. The only questionable thing I have found is that when I pushed that long metal spring in the filler tube, at just the right spot it will make the sound of air sucking in or out. This is with the long spring pushed maybe a foot or two down the filler neck.

When I push the spring in the filler tube even 5 minutes after trying to put gas in it you can clearly see there is a lot of gas in the tube as the spring comes out soaking wet.

I'm at a loss here. The only thing that makes sense is that the tank is completely full, but again he swears it is impossible.

I've heard something of a rollover mechanism to prevent gas from coming out, where is that located, and could that be causing the problem?

I would check to see if the gauge was bad. Then if that wasn't it then my next sugestion would be one of the wires broke. Lastly the sending unit may be stuck. GL

Thanks for the reply Eric.

Now this is probably a dumb question, but could the gauge being broken effect your ability to phisically put gas in the car, likewise for the sending unit? Or are you mentioning those things in the off chance he was wrong about the fuel level and it is in fact full of gas?

Originally Posted by scottydoggs

sounds like its full. if the gas gauge is always set to full the sender is shot. set the trip in the car run it a 100 plus miles, ( to run the gas level down) then open the trunk take the rug out and open the trap door, the pump is right there, 20 minute job to change the pump and sender. make sure your parked on level ground when taking the pump out.

the sender has a float on it, and has nothing to do with fuel entering the tank.

Thanks scott. I think your right, and that is exactly what I told him to do about 5 minutes ago.

Side note....I was pleasantly surprised how easy it was to access that fuel pump.

that's just there way of telling us that eventually you will replace the fuel pump lol