Cold Running Problem, Please Give Any Ideas

1988 RX-7 Non Turbo, Auto, A/C 40k on engine.

Little longer than normal cranking to start. 15 to 20 seconds till it starts.

Once it starts the Idle goes up like normal.

If I touch the throttle it dies. Will also dies after 30 seconds or so but, will restart. Touch throttle again it will die. If I keep it reved up to 3500 RPM will stay running. After 4 or 5 min. it runs and starts fine unless it sets till stone cold.

Compression is 105 psi to all 3, both cylinders with valve core removed.
New:
4 Fuel Injectors, Coolant Temperature, fuel pump, fuel filter, fuel pressure regulator.
Used:
ECM computer, throttle sensor

Adjustments:
No codes
TPS set to spec. (both lights on then set to 1 light on)
timing at spec. Lead and trailing
Fuel Pressure in spec.
vacuum to pressure reg. off when cold
no vacuum leaks found
idle speed 750 RPM
Variable resistor set to slightly rich.
Air flow meter by-pass screw closed down as far as possible to make vain move and record as much air going in engine, Richer.
Using good premium gasoline
Tune up parts good
firing order ok
EGR closed when cold
Air flow flapper moves easy
when I add propane it starts right now

I AM RUNNING OUT OF THINGS TO CHECK HELP!!!!

Question
Trying to correct cold problem!
Also are the secondary injectors used to cold start?

what follows is idling problem when cold ... may not be exactly what you are talking about.

well, when engine is cold, the idle should is held high mechanically by what is called the thermowax system on the firewall side of the engine .. as the wax inside warms up, it releases a cam that made the idle higher than usual .. it's explained in the Factory Service Manual (fuel and emissions system section) or Haynes. it's also called 'fast idle'.

idle is also higher if the coolant temperature is low ... the sensor involved is the water thermosensor behind the water pump near the alt.

to a degree, the idle is also raised if the dynamic chamber temperature is below some threshold .. the sensor is on the side of the dynamic chamber driver side.

Download the factory service manual 'fuel and emissions' section and look for troubleshooting 'rough idle with cold condition', that will give you even more things to check.

The fact that it takes 15-20 seconds to start is not normal at all. Do you have some kind of pressure reliever in your fuel system ? or do you turn off the car by switching off the pump feed ? I would think it's a fuel delivery problem either at injector level or pump level because if you crank for that long, it should flood under normal conditions. are the plugs wet if you stop cranking right before it starts ?

maybe you should check the basics including timing, etc.

H.