89 Buick Skylark

I think its important to give some back history as to what recently has happened to my car so that it may help to see what the cause of the problems are.

Recently my car was caught in a flash-flood incident, the water only got up to the bottom of my car door but it was just enough to submerge the muffler. But that's not the main problem just the back history since my car works fine now, all that was needed was a new battery and some time to dry.(I'm mentioning this since it could be related to the problem at hand)

The problem at hand is that recently I've got 2 problems with my car(it seems they might be related, might not tho). One is that after i put coolant in the tank the 'low coolant' sign seems to pop up every now and then. The second problem is that the car has been having problems starting up the engine recently, i believe the starter is okay, i hear it starting up but the engine doesn't start, it often takes many tries(up to 10 Min's to get it to start today) and it will eventually start but that worries me greatly since it sounds like its not a good idea to continually try to start it when the engine doesn't start right off the bat.

Any personal experience with this? ideas? advise? theory?

try checking your fuel pressure there should be a threaded conection on the fuel rail with a black cap on it.
some auto part stores rent out this tool or borrow them free.
get a haynes manual and look inside for the proper fuel pressure spec and after car sits a day without driving check the pressure before starting.
it should be close to what manual says. if not you have a bad fuel pressure regualtor.
otherwise if the engine seems to crank very slow you have a starter on the way out.
if its misfiring at all this could be a igntion issue otherwise i would say it sound most like a fuel issue