I have a 97 rs and my tank builds of a very significant amount of pressure. when I take the gas cap off it releases air for a good 3 to 4 seconds. I have seen pressure build up in other cars and never thought anything of it but it just seems like a lot of pressure for this one, more than should be, i feel. what do you guys think

 

Alot of it has to do with the temperature outside. With the warmer temps and low amounts of fuel in the tank will allow for more gas vapours inside the tank. So I wouldn't worry about it.

 

yes it is warm outside i live in phoenix az

 

Warm it's probably extremely hot out.

 

na its a little hot it has only gotten up to 108 so far

 

test your evap system and your gas cap. my evap was failing and effected my fuel pressure. https://camaroforums.com/forum/lt1-l...-system-51219/