Hello,
I'm new to the forums and am looking for some help regarding my Camaro.

The car is a completely stock 1992 RS with the 305 V8 and the crappy electronic fuel injection. I am the second owner and it only has 15K original miles, so it is like a new car in many ways. I have noticed that it often seems to have quite a significant vacum built up inside the gas tank when I open it to refill, makes a very noticeable sucking sound when opened. I also find it odd that it seals so well to create this vacum but fuel routinely exits, sloshed out on right turns when when the tank is full. (how is that possible?)

The problem is that it occasionally stalls and will not stay running. This has only happened to me once but it had also happened to the original owner on at least one occasion.

The scenario as it happened to me: Approximately 80 degrees F ambient temp and stopped in traffic waiting for a light. Had approximately 1/8th (or a little more actually) of a tank of gas reading on the fuel gauge. The car suddenly died without any fanfare or warning. The engine would re-fire but would not stay running more than 2-3 seconds (basically fire up and just immediately sink back through idle to dead).

The previous owner had described a similar incident and remebered that removing the gas cap and putting it back on seemed to make it run again. I tried that with no luck. It made a large sucking sound indicatuing a significant vacum built up in the tank as usual (or maybe even moreso than usual actually). A helpful stranger helped me push it out of traffice and after calming down for a minute I decided to try running it without the gas cap. Success! It would run without the gas cap, so I was able to drive a few hundred meters to the nearest gas station. I filled up and it ran fine the rest of the way home (about 10 miles) with the gas cap back in place. It also ran this morning and I drove it about 25 miles with no problems.

So are there any known problems with this generation Camaro gas caps, fuel system venting (vacum), low fuel levels, or a combination thereof? I'm really kind of concerned about this and I have a hard time trusting the car even though it runs great most of the time.

 

there is a vent that allows the tank to suck air without expelling gas. its located just in front of the tank close to the other fuel lines. maybe it isn't fuctioning or has so mud or crud stuck on it.

 

You may have the insne GM gauge that shows 1/8 of a tank when it is actually out of gas. GM istalled goofy gauges on their cars to make the driver belive the fuel mileage was better than what it really was. The gauge would drop very slowly to the 1/2 mark, and then go right to empty in kalf the time it took to go from full to 1/2. The hissing is typical of an empty or almost empty gas tank. So I just think you just ran out of gas.

 

Replace fuel filter, if you have not done it. Blocked filter could be your problem.