1995 Blazer Starts but wont Run
 

Hello Blazer peeps, new here. I am fairly versed in self repairing vehicles however, I just purchased a 1995 Blazer that ran the first day and on the 2nd day it had a rough idle then eventually stalled. I have replaced the fuel filter, and now it is just Starting and stalling in the driveway and now I am at a loss, as you know it is not Spider Injected, so my question is what would cause this to happen? I am already going to replace the EGR and I have checked for any vacuum leaks. MAF Sensor is good so is the injection. I don't have a fuel pressure test kit and I'm not throwing any codes unless the truck stalls. I currently have the poor thing torn apart searching high and low to find the issue. ANY AND ALL Help is welcome. I'd really like to get to the bottom of the issue but I currently work 7 days a week so I'm trying to get an answer from the pro here on the Blazer Forum. Thanks in advance everyone!

Can you hear the fuel pump when you turn the key on?

Yes, fuel pump is turning on. We are going to replace EGR in the morning and going to do a fuel pressure test

My old boss years ago had a '95 and it used to get carbon "rocks" stuck in the EGR valve all the time. I had to take off the valve and remove them every couple of months or so, just so the thing would run. And that EGR valve wasn't super easy to get to, IIRC. Your problem sounds more like it's losing fuel pressure, though. The fuel pump runs for a few seconds when you turn the key on, but then it shuts off unless the engine is running. It sounds like yours doesn't "know" the engine is running. I don't know if it uses the oil pressure switch (old school) or the crank sensor signal, or what, but it will be obvious on the fuel pressure gauge if that's what's happening.

Update*
We replaced the EGR Valve, Blazer stays running now but seems to have an evap leak or may need to replace IAC. Still working on it hopefully she improves. Gonna take it out and see if it can move under its own power today. I did notice a short curved tube that was just placed under my vortec cover, so im going to figure out where that goes.

Update
 

so ive replaced EGR and IAC and Fuel Filter. Im not throwing any codes by the Blazer is still stalling and idea what it could be?

Too many options at this time.

Need to make sure fuel pressure is correct.
AFAIK the 95 were all spider injected. TBI was not an option on the 2nd gen.
What codes does it throw?
How do the spark plugs look? (at least those which are easy accessed.

What comes to mind:
- Electrical sensor inputs from the engine harness. Has it ever been changed / tamperd with? Broken, chafed wires? Damaged protective sleeves? Connectors?
- Vacuum lines are notorious to rot away. Also the connection grommets crack and can cause havoc.
- Ignition base timing