Hello everyone, I'm the proud owner of a 1992 Z28 Camaro. I'm new to the forum and I wish I was introducing myself under better circumstances.


Late last summer I had my fuel pump replaced as well as a fuel injector. The garage where I got my work done is around 25 miles away from my house. The car ran fine on my way home, but when I got about a mile away from my house I heard the fuel pump start to squeal and when I pulled in my driveway and shut the car off I heard what sounded like air coming from the gas tank every 30 seconds. After 5 minutes or so this stopped. I removed the gas cap and a bunch of air came rushing from there as well. I asked around and was told that the fuel tank vent valve was faulty. I probably should have replaced it, but it was getting close to the time when I was going to put my car into storage for the fall/winter so I decided to hold off. The few times I drove the car before storing it, it drove fine other than the air noise when I'd park it.

I got the car out this past May and drove it a few times over the past few weeks and it continued to drive fine other than the air noise again. Then just last night I took it for the longest drive I've driven it since bringing it home from the garage last summer. I drove it around town for about 10 miles. I stopped at a store and when I went to leave the car didn't want to start right away. I cranked it about 5 times and it finally fired up. On the 3 mile drive home the car ran fine, but by the time I got it home the fuel pump started squealing again and when I parked it the air started rushing from the valve. I took the gas cap off and air came rushing from it as well. I started it up again for about a minute just to see how it would idle. It idled fine, but all of a sudden the rpm's dropped and it died. I couldn't get it to start back up. I let it sit for about an hour and tried again with no luck. I went out this morning and tried and it fired right up like nothing happened.

Would the faulty fuel tank vent valve cause the car to not want to start? I was thinking maybe it was building up too much pressure in the tank and was affecting the fuel pump due to the faulty valve and that was causing it to not want to run. Or is the car not wanting to start just another problem that is totally unrelated to the faulty fuel valve?

Thanks, and sorry for the long post.

 

check for fuel in the oil. sounds like a evap issue. have a look here. Vacuum lines schematics shows evap schematic for your year at the bottom. there is evap tests for the 93 in the how to and faq sticky in the 4th gen general section. i had a similar issue where my fuel pressure went up after i shut the motor off. that should not happen. it may be whats going on with you. pressure gets so high it floods the motor.

 

Thanks for the reply. I was looking at the diagram you provided and I happened to remember that I noticed last summer that one of the hoses leading to the charcoal canister wasn't hooked up. If memory serves me right it was the top one that leads to the throttle body. I'm guessing the previous owner was the one who did this because I know I didn't do it. I hooked it back up and not too long after is when the symptoms began. Is it possible that the car was doing this for the previous owner and he unhooked it to remedy the problem? Or would this have no effect on the situation?

 

i think what diconnecting hose would do would be to vent gas fumes to the air. not safe. test the canister purge solenoid and tank pressure control valve. is the air coming out or going into the tank when you open the cap.

 

When I take the gas cap off the air comes out.

 

Just a quick update. I was looking under the car and I noticed that there's no heat shield in between my muffler and gas tank. Perhaps when I got the new fuel pump installed last summer they forgot to put it back on. Is it possible the heat from the muffler would be cooking the gas tank causing the gas to heat up and cause the problems I'm having?

 

Very possible, and may even get a bonfire going. All things working properly there should minimal pressure in the gas tank. The EVAP system is supposed to let the gas fumes in the tank go to the charcoal canister and get absorbed by the charcoal. On a programmed schedule the purge valve is opened and the fumes are vented out of the canister and into the intake. If this fails to happen pressure can build up in the gas tank and cause flooding and hard starts.