trouble starting

01 blazer. starts fine first time ,run to operating temp ,shut off and let sit for a while (1 or 2hrs)try to restart ,it cranks over and over before starting, just cranks or starts weak. any one have any ideas thanks. it only happens when car runs awhile then i shut off and cools to around 100 derees on temp gauge. once started runs fine till i shut off again

I have the same problem except my Blazer is a 96

I would look at fuel pressure...you may have a weak fuel pump

my fuel pressure is 62,key on engine off, checked yesterday. my gas mileage also stinks,12mpg.changed plugs,they were black sooty.any help

Sounds like a fuel leak inside the upper intake...
Sorry to be the bearer of this news...
You may search this tread about CPI injectors and nut kit...and fuel pressure regulator...Best Wishes...

I am having a similar problem and it was NOT the CPI unit. I am looking at the ignition right now.