95 Chevy Silverado 5.7l tbi rough start, idle, acts like it's flooding then dies.

[JimGotfryd]

Will start cold, idles a little bit rough, will rev up nicely. As it warms up the idle gets worse won't rev up then dies. Acts lie it's getting too much fuel. Injectors look like they're spraying a lot of fuel. New injectors, fuel pressure regulator, idle air control, map sensor, temp sensor, ignition control module, EGR valve, and ECM. Also have new plugs, cap, coil, rotor, starter, serpentine belt and tensioner, fan clutch, alternator.
Truck ran fine, always dependable. Sat for a year after Dad passed, now it won't run more than a few minutes without loading up and dying.

Cousin was just here and thought it might be the fuel return line plugged or kinked. Restricting the flow could cause the same issue. Possible?

 

[WICruiser-97]

Look at the plugs to see if you can confirm that it is stalling rich/flooding.

Your description sounds more like too little fuel once it gets off the cold start fuel delivery map.

 

[PlayingWithTBI]

Check your CTS next to the T-Stat on top. It tell the ECM the engine temp. If it's (or the wires are) bad, the engine will think it's still -40 F and pour the fuel to it.

 

[JimGotfryd]

Check your CTS next to the T-Stat on top. It tell the ECM the engine temp. If it's (or the wires are) bad, the engine will think it's still -40 F and pour the fuel to it.

Got a new one in it. Wires look good too.

 

[JimGotfryd]

Look at the plugs to see if you can confirm that it is stalling rich/flooding.

Your description sounds more like too little fuel once it gets off the cold start fuel delivery map.

Plugs fouled with fuel.

 

[Schurkey]

Connect scan tool, verify EVERY sensor and computer output.

Assure that the injectors don't spray/leak when the ignition is on, engine not cranking or running.

Wouldn't hurt to verify fuel pressure.

Check the distributor for broken magnet by the pickup coil.

 

[WICruiser-97]

Would be a good idea to check that the fuel return line is not restricted.

Unfortunately "new" does not always mean "good" so a scan tool check of what the system is seeing for coolant temperature, etc. would be a good idea.

Is there more information available regarding why all the parts changes after it ran fine before sitting for a year?

 

[MANIAC]

Hey guys I have a 95 k2500 suburban 350 I recently rebuilt it and replaced everything top/bottom end and yes I do mean everything but the O2 sensor which i already checked and it was good, and the purge valve or whatever the sensor the EGR plugs into is called I have had a hard time getting the timing set at zero due to the difficulty im having trying to get it to idle but the timing is within 5 to 10° BTDC so should still be close enough to start, earlier today after replacing the fuel pressure regulator/fuel diaphragm It finally started and ran like a beast I even started it three times just to make sure I wasn't going crazy but the driver side injector o-ring was leaking so I replaced it 3 hours later, but after I replaced it, now it back to not wanting to idle and I'm stumped

 

[Schurkey]

95 k2500 suburban 350

I recently rebuilt it

"It" meaning "the engine"? Did you degree the cam, or just take a shortcut by cramming it in "dot-to-dot"? What is the cranking compression pressure?

and replaced everything top/bottom end and yes I do mean everything but the O2 sensor which i already checked and it was good, and the purge valve or whatever the sensor the EGR plugs into is called

The EGR does not plug into a sensor. It plugs into a vacuum solenoid. Does the solenoid work? Shuts off vacuum when not powered, allows vacuum when powered?

timing is within 5 to 10° BTDC so should still be close enough to start

You should be able to do better than that, but yes, that's close enough to run.

Did you plug-in the timing connector after setting initial timing?

Did you check to see if the timing mark on the damper aligned with the "0" on the timing indicator, when the #1 piston is at true TDC?

earlier today after replacing the fuel pressure regulator/fuel diaphragm

What is the fuel pressure?

it back to not wanting to idle and I'm stumped

If you're going to tag-onto someone else's thread because your symptoms are similar, be sure to follow the guidance given previously.

Plugs fouled with fuel.

Good guess. Verify this when you pull the plugs out to check cranking compression pressure.

Connect scan tool, verify EVERY sensor and computer output.

Assure that the injectors don't spray/leak when the ignition is on, engine not cranking or running.

Wouldn't hurt to verify fuel pressure.

Check the distributor for broken magnet by the pickup coil.

^^^ All that. Add-in checking spark power with a spark-tester calibrated for HEI.