Thanks Ralph....
The fuel filter is new, and the injectors are new. It was the injector change that breathed life into it again. Pressure on the rail is 40 pre-start and 35ish while running.
I just did another test and I want to add to my description of having the pump the gas to keep it running....
If the revs are high enough (above 2000) it will rev normally when I press the pedal and very responsive. Anything below 2000 and it bogs before revving.
After that test I started to wonder if there is TOO MUCH fuel and that's why it's bogging and stalling at lower rpm? Is that possible? Does FPR = fuel pressure regulator?
The injectors spray as much as the ECU tells them too, correct? Is there some other system or sensor that could be telling the ECU to spray too much fuel?
It starts on it's own and WANTS to idle now, which is an improvement, but it dies within 5 seconds if I don't pump the gas even though it's trying like hell to hang on. The exhaust smells rich to me BUT I am no expert on that. Lots of moisture on the floor under the mufflers, and both mufflers are equally hot after the test. The cats have already been removed from this one.
The ECU makes assumptions; when warm, it can adjust the fuel flow a bit (something like +- 40%, but I'm not sure on that number; one of the tuners here can correct me!) but until the O2s kick in and it goes closed loop, it has to guess.
FPR == Fuel Pressure Regulator.
35psi? Is that relative to atmospheric or to the inlet line on it (the vacuum line on non-boosted applications; the one it uses to reference the engine's plenum vacuum or pressure to adjust the pressure to the appropriate level)?
*checks book* OK, 30-40 PSI while running, 35-40 when Key On Engine Off. Methinks the FPR MAY be passing too much fuel through then. If so, it may be overloading on fuel; when you open the throttle, the TPR tells the ECU "Moar fuel! We gots air INCOMING!!!" and so it enriches more, but when you release it, there's a moment when the fuel drops, but the airflow hasn't, so it runs better.
And at higher speeds, the overloading might not be as noticable. (Greg Banish's book on EFI in the intake is ... illuminating on how this can cause a problem.)
Are the injectors factory replacements? Or aftermarket? Do you have a tune for it yet?
RwP