Calling all tech wizards, here's a doozy....

OK... you have base timing set properly...

Keep your timing light on AFTER the SPOUT is reconnected.

You should now see timing advance beyond 10 degrees.

Have a friend or you and your 6' arms open the TB...we should see more advance.

Let us know what your observations are ???

For Shyts & Giggles... and forgive me for asking...have you disconnected battery for 15 minutes to clear KAM ??? There's never any harm in doing this...and I would suggest it before following the steps I suggested above.


It's Beer:30 here... catchya later

-D
 
The timing does change once I put the SPOUT back on.
This time I cleared the codes by disconnecting the battery over 15 min.

But the lingering problem remains....

When I first turn it on, it starts fine and if I mash the pedal it revvs up just fine, but after about 15-20 min, with or without the SPOUT connected, it slowly begins to idle lower and lower, shaking violently, and if I mash the pedal it sounds like it slows down even further, until it finally just dies.
After that, I cannot turn it on anymore, I have to wait a long time to be able to do so.

What are these symptoms indicative of?
 
Without wading back through, I can't remember if you replaced the TFI module on the distributor or not. These units are known for warming up and then flaking out. Turn the car off and let it sit, the TFI (Ignition Module) will cool off and behave until it gets hot again, then flake out again. Might be a good prospect to be causing your problems. Just a thought...
 
Well, it's a brand new MSD Pro Billet 5.0 Distributor, and it came with a TFI module. Although it's new, I wouldn't rule out that it might be damage (who knows how long they remain on the shelf at Summit warehouses).
I will say this, after it dies, the distributor is REALLY hot to the touch.

I'm gonna try a new one I had bought for the original distributor, see what happens.
 
Something else, when the car first turns on, the fuel pressure is between 35-40 PSI, but right around the time that it shuts off, the fuel pressure is between 50-60 psi.

Is that too high? Am I getting a rich condition? All I've changed fuel-system wise is the fuel pump (255 lph) and a fuel pressure guage at the scrader valve. I haven't added an adjustable fuel-pressure regulator.
 
I just found out something about open loop and closed loop.

It seems that while it's in open loop, it runs, but when it hits closed loop, is when it dies. Would would cause it to die once it hits closed loop?
 
Sorry DREDD, I missed that you had the MSD Billet Dist. hence a new TFI. From what I've seen some folks swear by the MSD Dist. and some have had troubles. I still have my stocker so I can't say one way or the other.

Man, that fuel pressure seems way too high. Mine is about 30PSI at idle with the vacuum line on and jumps to about 39PSI with the line disconnected. Pull the vacuum line off of the FP regulator and make sure it isn't sucking gas in the line (ruptured diaphram). Have you pulled the codes yet ?
 
What was the outcome of this? I know this is being brought back from the dead... I think I am having issues just like this too...
Please start your own post: digging up old dead threads like this one just causes confusion and the date on it causes people not to post answers.

If you like, click on the link that goes directly to http://www.stangnet.com/mustang-for...-checklist-for-fuel-injected-mustangs.787471/, Cranks OK, but No Start Checklist for Fuel Injected Mustangs. It has everything you need to find and fix no start problems.