I have a 2004 blazer that cranks but wont start. Was told to spray starter fluid in intake and if it started than fuel pump issue. Removed one plug wire and have spark. Sprayed fluid in intake and wont even try to start. Havent done a fuel pressure test yet.

 

Keep us posted after you check the fuel pressure.

 

Did you reassemble the air intake before you tried to start it? My '96 has a MAF that has to have air across it to run. Unhook it and the engine won't start. I hope an '04 is a little more advanced but one never knows.

 

How can I test pulse to the injector