sometimes when i go to crank my car up it wont start.. i thought it was the starter.. so i replaced it.. but it still does.. when i turn the key.. the lights come on.. radio works.. and all .. it just wont crank.. its like i have to let it cool down or something.. what could this be..

 

do you hear a loud clicking noise.? or is everything dead quiet when you try & crank. (your engine)

 

everything is quiet.. no clicking

 

do you have vats? might be problem with it, bad lock cylinder, heat soak problem?

 

yeah possible VAT (vehicle anti theft)
Just wondering if you have a voltage drop when you crank if you have it means the power is getting to your starter & it maybe your solinoid , although you said you changed ya s/motor.
mmmmmmmm tricky one.

 

I have the same exact thing, made 2 posts about it recently. My mechanic is gonna check it out again next week.