98 BLaser LS 4.3L Vortec cranks but no start
 

So i am having issues with my blazer, its been running great other than the fact i came home went to go start it and it just cranks over, I checked the ecm, i checked the coil, the fuel pump is kicking on..But just cranks will not start Thoughts?

Is there a blue, not orange, spark at each spark plug? Have you checked fuel pressure and leakdown? This link explains: https://blazerforum.com/forum/2nd-ge...eakdown-88305/ Post all 4 readings. Has the check engine light been on recently? Are there any codes in memory?

Check engine light has been on for awhile it was the P0452 error for the low pressure, I replaced the sensor and still has had this error but has been driving, would not clear, been driving it like that for awhile, now all of a sudden it just wont start

EVAP problems will not cause a no-start condition, (There are other codes that will cause no-start). What about spark & fuel pressure?

I dont have a fuel pressure gauge but i have spark, when i push the buttun on the rail fuel does come out and you can hear the fuel pump kick on when you turn the key

dont have a OBDII reader either unfortunatly, only reason i know of the 0452 code is because of autozone

Do you want to fix it yourself or just ask for ideas about what could be wrong? Autozone has loaner fuel pressure gauges. Here is an inexpensive scanner. You have to do your part. See post from Captain. If you don't understand something, then ask.

https://blazerforum.com/forum/2nd-ge...-retard-90496/

If you simply want to ask what it could be.... Could be electrical, could be fuel, could be mechanical, could be security system. Where/how did you obseve the spark? Color? How did you check the coil and ECM? Need to know fuel pressure reading for certain. Post the 4 fuel pressure readings in Captain's link. It's where you need to start.

Well i pulled the top off and each injector turned the key no fuel coming out of any of hte injectors, pulled fuel lines and stuck in a bottle to make sure had flow, flow to the lines are good. I just took off the Fuel pressure regulator to check that.. so I have it down to either the injectors or the regulator? I pulled spark plug to check for spark, checked for spark off coil wire also,

96 up Blazers are notorious for both fuel and ignition system problems. They require a minimum fuel pressure to start and run, especially if it still has the original poppet type injectors no fuel at all can be delivered. Regulator can also be an issue. For this reason we recommend testing and reporting all 4 readings per the link. It is the ONLY way to truly know if your fuel pump and fuel pressure regulator is up to snuff. Since you had the plastic cover off, tell us if you have the type of injection spider (upgrade) where it has individual electrical connectors on the end of each spider leg (or not). If you are getting nice spark at the spark plug, then chances are a no start is likely fuel related. As an aside, as I understand it the security system disables injectors. Can use an injector test light to check if injectors are receiving the injector signals. Since you are getting spark, you should also be getting injector signals if something is not interfering with them.

It would be very strange for all of the injectors to go bad. The only way to truly test the fuel pump and pressure regulator is through the linked tests. Doesn't really cost anything other than a few fittings - only work, but it seems you are not afraid of a little work. Autozone and Advance and others have loaner fuel pressure gauges with deposit

Good luck!

I agree. Removing the regulator isn't going to tell you a thing. The original injector poppet nozzles need at least 40psi of fuel pressure before they will squirt any fuel at all. If you only have 35psi at the service port, it will squirt out of the port, but the injectors will not squirt fuel into the combustion chambers, and the engine will not start. You need to do some proper testing, or some proper guessing, to get her running again, your choice. We can help you with the testing, but you're on your own for the guessing.