Running TBI on SBC
Long story short, car was down all winter to sump the tank and put in a new fuel system. It's September and I still have no start.
I have just under 20psi to the injectors. I have spark, air, and fuel. I can crank and get a nice cone from the injectors for the first second but it seems to taper off and turn into a dribble for the next but comes back to a cone.

Pulling injector wires to burn unused fuel gets a quick rev out of it.
Starting fluid with get a couple revolutions that sound good also.

I've burned a chip to account for the increase in fuel pressure.
I'm down to throwing parts at the ignition system mainly the control module since that is the common link between fuel and spark. Otherwise the injectors could be dirty inside.

I have tested:
Ignition control module
Primed oil system and verified timing(three times)
Voltages for ignition system
Checked fuses
On ALDL all my sensors appear good.
Pulled injectors to make sure the injector pod and screens were clean

Any other thoughts would be great. From what I can tell I've been through everything. I have injectors for a 350 in it now but could go to 305 or even 454 to verify operation.

 

Should be 11 - 13 psi. Too much fuel

 

This tells a specific story: that story being, YOU HAVE SPARK.

This reasonably evident fact is not consistent with:

Leave the ignition system alone and concentrate on a fueling problem. Whether that is too much fuel, too little fuel, fuel for a short time and then no fuel after that, or whatever; it's a FUEL problem.

Quick way to verify all of the above is, unplug the injectors; pour an ounce of FRESH gasoline down the intake; try to start it. If it starts and runs until the fuel is gone (2 or 3 seconds or so), you have just eliminated ALL possible "explanations" that involve the ignition system.

See my signature for some help involving logic. Pay attention to each word individually. The word that is most important here is "all": if you have a symptom but your "explanation" fails to "explain", or worse yet, your "explanation" AUTOMATICALLY requires some symptom to occur but it doesn't, then the "explanation" is wrong and you should look elsewhere.

 

I think you are right about the fuel and I have suspected that as far as the cause but I'm not sure how to go about correcting it.

I'm running an MSD 2555 pump for my LS swap coming up. I have that running into a FueLab 25-90psi regulator. Setting that as low as it will go in parallel with the TBI sets me around 20psi. So from what I know I am running wide open as far as the TBI regulator and whatever does not push through there goes out the FueLab regulator.

Maybe the pressure is dropping at the TBI but not at the new regulator where I have the gauge.

I'll try changing up the plumbing a bit and see what happens. I have a few ideas I can try before getting drastic.

 

Well, first step would be, figuring out what it is.

From your description, could be any one of 3 things:

1. Not enough fuel
2. Too much fuel
3. Fuel starts out right but then disappears after a few seconds

All of which would likely stem from VERY DIFFERENT causes.

Figure out which one it is, and then we can go down the correct path the first time, without hitting a bunch of dead ends along the troubleshooting path.

 

Shortly after posting I thought about your quote: The simplest explanation that fits all the facts is probably the right one.

So I went out and checked what I had not looked at before... the fuel lines. I guess at the time I thought the return line should become the supply line. So now it runs but is rich. I should be able to get it into closed loop and adjust my BPW from this point.

Honestly I've only been fighting this off and on for a few weeks. I was getting very close to using a hammer though. Thanks for the help.

 

Glad it was something simple and eeeeeezy to fix.