I have been have a terrible time getting my blazer to start. It will crank the battery flat and not fire. If I hook it up with jumper cables eventually it will fire.
I have; Replaced the air filter fuel filter distributer cap and rotor arm and spark plugs, cleaned the MAF (twice), had the fuel pump checked. Also ran injector cleaner though the system.

For a while it would start with a spray of something volatile down the throttle body (I was using throttle body cleaner on advice from a guy at Advance), but this seems to have stopped working now.

It is for the world as if it is not getting fuel at start up. But it runs smooth and idles even, doesn't hunt or pink. Indeed it is running like new, once going. So as I understand it it doesn't seem like a fuel delivery system failure.

Is there a particular sensor failure that would cause this specific problem?

I don't know much about this particular engine but does it have a separate carb jet for starting if so could that be blocked?

 

Read this, follow the steps, come back to this thread and let us know what you found.
96+ Fuel System Diagnosis

 

You don't want to keep cranking on the starter, that's how you burn it up. This sounds like a fuel pressure issue.
rriddle left you a good link to head over to.

 

Thanks.

I think. I was hoping for a ten dollar sensor (if there is such a thing on it) to have blown or something.

I was afraid it might be the fuel pump but assumed because a mechanic had checked it it was ok. I didn't know to ask if they'd actually checked the pressure.

 

Was indeed the fuel pump. Thank you for sharing your knowledge it probably saved me a lot it diagnostic fees.