My car (2002 Camaro SS) is more of a garage queen as of late and is only driven about 500 miles a year. The car only has 55k miles on it. I have had an issue over the last year where the car will start fine on the first start but subsequent starts the car will barely idle and stall out and then on the 4th start runs fine. The car once started correctly idles fine and has never stalled on me while driving. Sometimes feathering the gas pedal will help the car stabilize when it doesn't start properly.

Tonight I performed the following. I was hearing a hissing sound which said to me vacuum leak. Low and behold the tube that goes into the pcv housing was not fully seated. I resolved that issue and replaced the pcv valve. Then I went onto the idle air control valve. I pulled it out and cleaned it out using a carb/throttle body intake cleaner and I cleaned inside the housing as well. When I started the car the first time the idle was smoother and higher on initial start than it has been. I also resolved the hissing sound. I went around the intake and sprayed the carb cleaner over connections to see if idle changed and there appears to be no vacuum leaks any longer.

I thought I was in the clear so I shut the car off and started it back up. The car idled rough and stalled out. I then tried starting it 3 more times and the same scenario. Then the car started ok again. I revved it up a bit and then I had a backfire in the exhaust and it seems like the computer reset, all lights flickered service engine light briefly came on and disappeared. I believe the backfire to be from an exhaust leak just before the pipe that connects to the pipe before the muffler which I plan on fixing in the near future. I recently had a new y-pipe with high flow cats and all new Oxygen Sensors installed but this problem was present before that change. I replaced the plugs, wires, gas filter, and air filter about 3 months ago. The old plugs were in great shape so I probably wasted my time doing those. I also cleaned the MAF sensor with MAF cleaner.

I was doing some research on the issue I have been having with the hard starts and I heard that replacing the cam sensor has resolved a similar issue for others. Anyone have any thoughts on this?

 

Since this is in the Tuning section, has the tune been messed with?

If your car sits most of the time, I would suspect bad gas or something fuel related. Since it starts initially and THEN dies, you can rule out ignition components. Empty a can of seafoam (or whatever fuel treatment) in the gas tank, then go fill her up and have yourself a pleasure cruise. Filling the tank will help mix the seafoam in with the gas. Driving around will allow the seafoam to thoroughly contact all fuel delivery components (pump, injectors, etc.)

Also next time you start it, check fuel pressure to rule out the pump.

 

I will check the fuel pressure and add some treatment and go for a long ride. I realized I probably posted in the wrong section. The car has never been tuned and has minimal mods. Air lid and high flow cats and y pipe. I was considering bringing the car in for a tune I did receive a rear O2 sensor code on the driver side. Which I had received before replacing cats and all 4 O2 sensors. Other than that no codes. I was going to move that O2 to another location to see if the code follows the o2.