Was reading some of the other posts, not sure any are same as mine.

Last week my Blazer, which has fired off almost instantaneously when turning the key since I have had it (2 years - has 85k on it) all the sudden wants to be cranked longer to start. When I say longer, I mean if it used to fire right away, now it just seems like it wants to go around all the way or more now before it fires...like holding in start for about 1.5 seconds where maybe it used to take .5 seconds. (About).

Runs fine, no power or other issues. I have not yet remembered to try letting the key be on for a few seconds before I crank it to see if it would be like a fuel pressure bled off type thing. My old 78 Nova has an electric fuel pump feeding a tri-power setup and I let it pump up before I start it.

Occaisional code of 440 for evap emmissions, but it's been like that since I got it, no mileage or other issues, I clear it now and then to check for other codes. Never had any others.

Thanks

 

So far today has started without the hesitation or the slightly longer cranking. Odd. Self fixing problems scare me!

 

That lasted a day....back to it again. Checked codes, none. Apply fuel injector cleaner.

Guess no one has heard of this...

 

Probably just time for a tune up.
When was it done last?

 

10k ago. I thought same thing, but it seemed to happen overnight, and when it starts, it's smooth, no issues. I keep thinking it just doesn't have fuel yet.

 

I've had ignition control modules act up some before they died. That's a more expensive guess than your fuel supply thought. A $20 harbor freight fuel injection pump test kit will tell for sure. Did you use an ac delco cap and rotor? 4.3 vortecs are fussy about that.

 

New plugs (that's an *** whippin) , wires, cap, rotor...same problem. Does run a little smoother, looks like it had factory plugs in it.

I have narrowed it down to starting after it has sat for a longer period like over night, or all day. Starting after an hour or two is fine. By the way it stumbles, it just acts like it doesn't have enough fuel, or there is air in it. No leaks, no vapor that I can detect, and it runs great otherwise, I pull a 6x10 trailer with my zero turn mower on it and the engine has all the power it is supposed to, no lack of go.

I'll keep working on it!