91 8V hard start long cranking on hot soak. cold great

[fixkick]

WELCOME !
Speed Density systems. (assuming good spark parts , tuneup parts good)
91 is easy to see injector leaks, key on 3 times no start, look at injector, no leaks, it's ok. (in that department)
1200, is wrong HOT there is a problem there.

Cold start , or any really , are all temp sensor based , for fueling. (tables)
i'd check the ECT first with an ohm meter.
i'd need outdoor temps, but lets do examples. pretend freezing day, in drive way parked.
32F (0c) i unplug it and it reads, 6000 ohms,(about) if more, the ECU thinks you are in Siberia and it will flood, check hot for 300 ohms to (both temp ends)
http://www.fixkick.com/ECU/temp-sensors.html
check IAT too.... on 8v its very important sensor.... same rules but is air temp not water. the IAT is a faster acting ECT.

flooding has many causes. too high fuel pressure tops list. 30psi is ok 60 not.
1200 hot? is bad, cold is normal until the IAC (thermal ) closes.
1200 HOT (is the ECU fast Idle pins stuck true state (a/c, and p/s?)
is the dash pot retracted, ? after start, after 5 to 20 seconds from start it must retract,
is the idle stop screw still at factory spec, TV valve closed 99.9% (.0005 gap in bore to plate) if the TV passes water past the plate (test) the valve is set wrong.
grimlins did that.

the 8v loves to race hot, with any air leaks, it RACES, finding them all is a small horror. for sure the idle speed controls are out of control. (servo loop dead)
and does prefect air fuel mixture, at all times.with leaks of air. Unlike the MPI G16B (leaking)

there are only 3 paths. to leak air. (photo below) (IAC + ISC + Bleed) no others!. (assumes all hoses good and gaskets sure) DP retracted !

here is my drawing off my TBI slide show.
TV is closed, it don't leak. (throttle Valve = TV)
IAC i closed above 150F water temp, if not the engine will scream hot.
the ISC is ECU totally controlled, unplug it, does the idle drop? to 400?
Pinch the ISC air hose, does idle go to 400 or 500 and nearly stall or stall? (all normal) if not you have leaks. VACUUM AIR LEAKS.
The last air leaks is the bleed screw, so screw it in , and bottom it out, (gently) this can cause the ISC to wake up. (as you screw it in)
once all leaks are gone (air) we then set the bleed screw, for 50% duty cycle and the ECU then keeps hot RPM at 800 all the time. (until a/c on or P/s over load.)




and frame 37 here. TBI xray view , is that not good ?
http://www.fixkick.com/fresh-air/Slide_S...ge_37.html

blocking the IAC ports to test it is no fun, its tricky
im idea of testing IAC is like frame 12 shows.
here
http://www.fixkick.com/fresh-air/Slide_S...ge_12.html

this port must not suck air, hot , over, 150f it is closed.
and if the water pipe is clogged it fails. hot water (AF coolant) must flow here.

frame 24 shows clogged up TV. causing fast idle if TV sticks open as does any of 3 throttle cables set tight not lose spec.
Throttle, A/T kickdown and cruise cables all 3 must be slack .

easy check 1.
keys in pocket.
off air tube. top
look at TV
grab DP rod and retract it by hand
the TV must be 99.9% closed, if not that be wrong. fix this first.