'93 regal gs start problem

Here's the senerio, I will take the car to the store, when I return after a few minutes, the engine will turn over normally, but will not fire. I repeat this a few times with no success, and the wait for about 10 minute. I try it again and it starts. It does not have this problem all the time, and has not done it when starting the engine cold. The GM guys have replaced the fuel filter, and say everything else checks out ok. Any ideas

Any codes? I assume not, if the GM guys checked all that. When the car fails to start you need to check for spark & fuel, one or the other, is missing!

i am having a similar problem with my 90 regal not exactly sure what it might be but i have an idea i am thinking the oil pressue sending unit might be having problems because if it doesn't tell the ecm that it has enough pressure the ecm will not let the coils fire for the spark i am going to try this with mine i will let you know what i come up with