Hi Guys - just a heads up - I also posted this over on TB - but so far no bites..I've seem some pretty sharp guys helping diagnose over here...anyone got any ideas?,

So I've been trying to "diagnose" a problem that I'm having with my 745t that's getting worse lately:

-Lumpy idle - sometimes nearly stalls right after startup, then recovers
-"balky" acceleration, especially under heavy load
-occasional misfire and backfire under highway speeds and loads - but always seems to clear up when I let my foot off the pedal (at that exact moment..)

What I have checked:

Fuel - 35-40ish PSIg at idle - both pumps are running, pressure somewhat drops when revving the engine, but can't watch it obviously when driving..

Spark - replaced cap, rotor, (bosch) wires (bougi) and plugs (bosch). Some improvement, but seems to get bad again later on..also replaced coil with a "used but good" one.

AMM - swapped with a known good, no improvement

Engine speed (RPM) sensor - no improvement

Power stage and RSR - no improvement

Generic 3 wire O2 sensor (bosch) from Ebay.. - no improvement

Checked/verified ECT sensor - proper resistence at ECU

Pulled each plug wire off at idle, and each cylinder seems to contribute about the same amount of power..ie idle fluctuated similarly for each one..which SORT OF rules out a dead cylinder I guess?
I went through the whole LH2.4 manual and checked and adjusted everything - found some improvement in fine tuning the TPS sensor - but still same behaviour at idle and under load..

The only two tests that weren't too conclusive were
1. While testing injectors resistence at pins 9 to pin 18 (supposed to be 4ish?) I was reading something like 65..however when I do the system check using the LH2.4 diagnostics, you can hear the injectors clicking..and I had them proffesionally cleaned about 3 months ago - so I guess I would have heard if they were damaged..
2. While trying to read O2 sensor voltage - I only got a -.5 volts from the O2 sensor..not sure if my multimeter just sucks at reading transient voltages or what, but the engine runs slightly worse with it unplugged, then changes a bit I plug it back in..

Anyways..probably have more stuff I've done, but that's enough of a novel for now..does anyone have any ideas? I feel like I've checked and or replaced nearly everything, and the car honestly runs worse now than 6 months ago!

Oh also - nearly all charge air hoses are new..as well as vacuum lines. Can't find a leak anywhere so far by spraying carb cleaner around..

Thanks for ANY help..would REALLY love to get this thing going and back to the reliable car it COULD be...

-Gus