I have a 4.3 6cyl. 2000 chevy blazer with the vortec. The regulator I hate to say is under the manifold with the spider injector. Im having the same problem with mine. The engine cranks but wont start. The pump is working and the filter was changed. Good luck Ive learned my lesson with this Chevy.
Here are diagrams to help you see what I am talking about.
Check out the diagrams (Below)
Please let us know if you need anything else to get the problem fixed.
Images (Click to enlarge)
Friday, December 28th, 2007 AT 8:45 PM