So I just recently bought the good ol Starship camaro 2.8l v6. Ran great at first but then started to notice her idle a little less easy (almost struggling) and the smell of gas was more prevalent.

Decided to fill her up not sure whether I was low on gas seeing how most of the gauges malfunction. That's when I heard the hiss after I opened the tank up. Figured it was running on fumes till I decided to check for the woosh sound again later that day, same thing happened. Felt like it was blowing out pressure instead of sucking in.

Any ideas? I was looking at replacing the iacs or the charcoal cannister filter. Am I on the right track or is there more I should be looking into.

I'm new to these third gens and, in general, cars all together so go easy on me...decided to make this a restorarion project.

 

This is one of the problems with these cars that we can't quite get a definite answer on. The evap canister could be the issue but I don't think changing the filter would help much. There's a white tank breather coming down by the driver side back seat floor pan but there's no way to get a brand new one anymore, I have the pressure issue as well and am tempted to take a good hard look at that breather

 

I'll have to take a look at that as well. Going to a garage tomorrow to take a better peak. Thanks for the suggestion. I'll be sure to update as I progress.

 

The gas tank is SUPPOSED to hold some pressure. That's how these cars were built. There is a tank vent like TylerSteez said. It's designed to hold about 1PSI of pressure before it vents to atmospere. It should open under ANY vacuum. It's basically a spring-loaded vent like you would normally find in the gas cap, but on 3rd gens the gas cap is a solid plug and the venting duties hare handed by this separate unit down by the gas tank.

 

Oh ok. That solves that. But I am still curious though why I still get an idle that struggles and the smell of gas while idling only. I thought the whole gas tank pressure might have been a part of the problem, but seeing how it's not I have nothing on where to go with these issues other than getting a new IACS.

 

Thanks for explaining that Damon, good info.

 

So the problems listed above have almost taken care of themselves. I assume it was the fuel system cleaning additive I put in the tank the other day. Only concerned because I've never had a car do that to me after adding in said cleaning agents. Picked up a Chilton repair manual today, heard people swear by them.

Thanks for the useful info guys.

 

No, maybe swear at them. Factory Service Manual (FSM), yes, go by them.

RBob.

 

Alrighty then, I'll get that as well. Thanks for the heads up, bob.