I have an 89 firebird with a 2.8L engine

Problem is when the car is cold...it takes a while to start...Engine rotates but does not turn over...have to try like 5 times before it actually starts

After its started...and I turn it off...It starts right away everytime...but if it sits for a while (an hour or so) ...again it takes a while to start

On a hot day (in the 90s or higher) it starts right away as well

What could be causing this? what do I need to check for?
or any idea of how hard of a fix it is?

 

im having a similar problem with my 5l,