no power

I am tring to fix a friends car. she had put it in a snow bank and now it will not go over 10 miles an hour.I have put some heat in the gas tank. The car will run at an ideal but when you try to push on the gas pedle it wants to cut out. I have tried to remove the fuel filter with no success. I am at a total loss.It is a 2001 pontiac sunfire.

Since it happened after the snow bank my 1st guess is the air intake is plugged with snow. I think the air intake is kinda low in these cars. Pop the hood and take the air filter cover off, leave it off and see if there is any change. Or if its possible, leave it in a heated garage overnight.