1988 Sierra: every now and then motor won't start

[droberson]

Although I haven't dealt with this specifically on one of these trucks, my Jeep was doing the same thing for a while. When the engine was cold, it would fire up every time. Drive for about 15 minutes and try to start it again, no dice. Sometimes it worked, sometimes it didn't. It turned out to be the neutral safety switch.

When it wont start normally, can you short the starter out to start the engine? That might rule out the starter for you at least.