[Involved] Crazy MPFI, mind of its own

[fmc351]

Yeah I know, Im a noob and hitting you with a problem, but hopefully someone here will know whats going on, before I beat the aging baldness and deliver my own. The things driving me nuts.

Starting problem
1988 EA wagon (S, MPFI, 5 spd manual), starts usually on the third turn of the key (I dont hold it cranking endlessly until it starts, i just wind it for a few seconds (maybe 5), then try again). By the third attempt it starts. Idles at about 800 rpm, then settles down to maybe 650 - 700. I have tried just letting the pump prime the lines, ie: key on until pump shuts off, then off/on again, repeat 3 times, but it makes no difference. Still takes three lots of actual cranking to fire up.

Once running, still cold
Once running, from cold, and slight downhill from home to the corner, I can 1/4 the pedal and it takes off and revs out to 4,000 no worries (I dont usually reline it, so it would likely rev harder). Once it warms up, it wont rev past 2,000. I need to ride the clutch to take off. Once its moving and if I slowly feed it pedal, it will rev past 2,000 but very slowly (like driving a diesel).

Highway cruising
While cruising on the highway (flat road at around 1900 rpm to do 100 kmh), it will cough, seems to cut out, fire up, cut out etc. Occasionally I can smell its leaning out, other times it uses excessive fuel. When it cuts out, if I take my foot off the pedal, and replace it down slightly it will take off, then cut out again, until it decides to run fine. It often runs absolutely fine too, but I can never give it a bootful and take off, it will just splutter.

Idle
It often idles fine, but occassionally it will hunt, or close to stall, then back to either 650-700 rpm or resumes hunting. But I can leave it at idle for 5 minutes and it just sits there idling fine, other times it will start hunting within 30 seconds or so of letting it idle.

Under Load
Theres a particular hill near home, if I take it at 110 kph, it may fly up at 110, other times it will drop back to 80 and I drop back to 3rd to hold it there, and it usually holds at 70-80 kmh.

Anyway, theres probably more symptoms but thats all I can think of now. Ive replaced a few parts, and used a few test parts, but cant correct it, it remains exactly the same.

Brand new parts replaced.
Dissy is a complete replacement from Bosch. Incl TFI, and hall effect, rotor button and cap
New champion leads and ngk plugs.
New bosch alternator (85 amp)
New VDO fuel pump.
Inlet manifold gasket.


Swapped injectors and rail for known working ones.
Have replaced EFI and fuel pump relays with known working ones. (Twice)
Same with fuel regulator.
Same with MAP sensor
Used a mates ECU (EA 3spd auto MPFI, mines a 5 spd manual MPFI). Numbers on ECU are the same, except for one letter. His is a 7a, mines a 7b, or vice versa)

Left to play with are.
O2 sensor
Coolant temp sensor
ISC solenoid
TPS
Throttle body. <<<<Likely, feels like a dead spot maybe, but doesnt explain the intermittant hunting, and occassional running fine, could be wrong though
Wiring

I looked for an airflow meter, but cant seem to locate it.

Any ideas. Or should I just burn it? Tell you what, ive come close.
Thanx in advance.