Ive got A 94 s-10 blazer with the 4.3. When i try to start it just cranks and cranks but it doesn't seem to catch. when it does catch it starts right up. I changed my coolant temp sensor at the front of the engine. could the fact that my gauge does not work be one of the problems and Is that sensor on my driver side of the block? Is this a starter problem or a senor problem? Thanks guys.

 

i believe all GM vehicles also have an oil pressure switch that prevents the engine from starting until oil pressure rises..

you might want to check into that

 

I have some new developments. When it is really cold outside ,like 20 degrees and lower, it starts up instantaneously. But when it is any warmer it takes forever to get started. I think it is adding too much fuel on startup. How can i get it to lean it out a little. I hope that narrows the possibilites down.