Ok, were do I start?? LOL

I own a 99 S15 blazer with a 4.3L engine. She runs like a dream until yesterday(6/9/2012) when I went to start it and got nothing. She is getting great fuel pressure up to the injectors(we checked). So I figured that just let her settle down and try again. Well I did and for some unknown reason, She flooded herself down to where she just cranks over but wont start.

I gave up for the day and tried it again today and she is still doing the same thing. Cranks like crazy but acts like she isn't getting fuel(which she is). Could my injectors be bad or is it an O2 sensor going bad?

Please help

 

https://blazerforum.com/forum/tech-articles-diy-29/96-fuel-system-diagnosis-23038/

That should help ya out. Key on engine off should be about 55 psi and no leakdown for 10 minutes. Post back your numbers.