I have an 1989 Oldsmobile Cutlass Calias it starts and run most the day then later on in the day it cranks but wont start. What could this be from and how do i fix it

Starter motor!

Sounds, like a faulty ignition switch.

i have the same car, TPS was the issue

ok!1st check all the spark plug cable, making sure the cables are in good condition, sometime the cables was wet & moisture inside, it doesn't pass electricity easily, so dry them by a hair dryer. it may help! as a old car that hasn't got a lot of sensors built in, it can be a bit tricky to solve the problem .

However if the old car can't start, it is concerning on ...Starter motor , the connection & condition of the spark plug + the cables , fuel pump, finally it may be the cars key chips that doesn't communicate with the car security system,so try to start the car with another set of car( it happens on a modern car)

After all the checking , then look into the distributer . It is not so expensive , before u replace it , mark down the timing ignition with a marker . It will help u to replace a new distributer back into the correct timing position as it was