So I have a 1995 blazer 4x4. Ive put literally everything into this thing- transmission,sensors,distributor,(cap,button), new plugs,wires, pcm, spider kit,fuel pump filter, fuel regulator sensor. I am totally out of options. It will run great for a couple days and then not start at all. New battery,starter,ignition. Recently it would not stary for a few days, went outside turned the key,it chugged sputtered but started up. I drove it down the road,it was ok for the few first minutes,then started sputtering really bad.so I brought it home and here it sits. Ive put so much money in this car and if it was not the only one I had I would have sold it! I dont know where to go from here. Am I missing something simple?please help me!

 

Welcome to the forum!
Sounds like we need to start at ground zero and diagnose the problem 1995 used 3 different computer systems, (one of the reasons Olds did not produce the Bravada in 95) and we need to know which system you have. They each have their own diagnostic and repair procedures and specifications. Does your engine look like this with "VORTEC" on the plenum?

 

Yes thats it!

 

This is a Central Multiport Fuel Injection system, (CMFI). It has one fuel injector that is batch fired and the system is controlled by OBDI engine controls.
Have you checked fuel pressure and leakdown?
Is the check engine light on?
If so what codes are in memory?

 

Fuel pressure is good, and well the check engine light was on, would come on and off alot. I couldnt tell you exactly what the codes are, but when I had it checked last it was for the fuel regulator and o2 sensor. Both were changed. Also a misfire,which the last mechanic had the plugs wrong.... Those were fixed. Im getting good spark also. I hope I dont sound dumb lol im a dummy with cars!

 

I had the spider kit thing changed literally 7 days ago,ran great for two days,wouldnt start. Wait an hour, it would start. Then it took me 3 days to get it started. Im sure the mechanic cleared the codes.the light is not on as of now

 

"Fuel pressure is good" Looking for exact numbers. As mentioned, 3 different systems, gotta make sure on all this stuff, starting with the basics. Key ON, engine OFF, fuel pump running: fuel pressure must be 55psi to 61psi and must remain above 50psi for 10 minutes after the pump shuts off.

There are no DTC's for fuel pressure regulator, somebody is pulling your leg. Need to know what DTC's were in memory.

 

Hmmm. Well I will have to get back to you on that, I have no way of testing it again right now. I have no help or anyone here with the correct tools.

 

Hi, i started this post a few months ago, and i'm still having trouble. Replaced fuel tank, pump, relay, filter. Pump is 57psi. The engine light is not on. Put gas into the tank and will hard crank but won't start.

 

If i leave it sit after cranking for a few days, it will run great but does the same thing after putting gas in it. Any amount