Car runs but when shut off and restart later it wont start..
 

The car is an oldsmobile 1998 alero and when you start the car it will start most of the time and run fine until you shut it off and wait about 15 minutes. Once you wait that long it will not want to start the engine turns over and over but the car wont start. If you leave it alone and retry later in about an hour it will start ok again until you shut it off then it wont want to start again.The tank is full with good gas and the fuel pump has been replaced along with the ignition coil and the oxygen sensor.Any ideas or tips would be helpful thank you. I do get a code in the electronic diagnostic machine that read code 171 which means lean... we checked all 6 fuel injectors and all read around 11.9 so it looks good.

Is the security light on?