Pontiac Repair: starting problem, pontiac firebird, battery cables

Question
i have a 1989 pontiac firebird 2.8 6 cyl. after driving a distance it won't start for 30-45 mins.  i replaced the solenoid but several dasys later it did the same thing. It seems to happen more when its hotter out. we put a heat insulated sheet around the starter which worked for about a week.  should there be a heat shield there?  or is it some other problem?

Answer
Hi Vicki:

I'm not sure if there was a heat shield on that starter motor or not This goes a long time back and Can't remember... Did you buy a "good quality starter" or a budget one? If it';s a low quality one you may have to go through several before you get a good one. there is a reason why they are cheap! I would also have the battery cables checked. You may have a cable with high resistance in it and that could be cauing your issue here. Another possability is a neturtal safety switch is bad.. Last possability is a security system failure.. When this will not crank doe the security lamp come on and or start flashing when it will not crank?