ok so I have a 92 accord, last summer I had to do an engine swap (to a F22a4)... ever since the swap it have been difficult to start when the engine is cold (the colder the weather, the more difficult to start). I usually have to "prime" the fuel by turning the key to the on position, waiting for the pump to start, turn to off then back on a few times. while I'm turning over the engine I have to pump the gas then hold it to idle at ~2-2½k RPM's for about 15 seconds for it to maintain it's own high idle till it automatically drops to normal idle without stalling.
If I try to drive before the engine temp at least starts to rise on the gauge, it has almost NO power until RPM's hit about 3k (if I try and let the clutch out to fast it will stall)... Once warmed up it runs/idles/accelerates almost like new... OHH and my MPG went from about 25-30 down to 20 if I'm lucky...lol

when I did the engine swap I replaced almost all gaskets/seals, fuel filter, plugs/wires, the fuel pump is a performance pump that I replaced less then 3 years ago...

EDIT:
My assumption would be that it's the injectors, but I don't have the money to waste on a "hunch"...lol

 

have you pulled the codes yet to see what the computer says is wrong?

 

so to pull the codes, there is a blue elect. plug RH kick pannel, you just place a jumper wire between two of the conections, right?

 

yes sorry, I forgot to list that, but I don't think it's relaited IMO, but it flags:
Code 6, ECT, Engine coolant temperature

 

yes I would say that is def related.
That is the sensor that the ECU uses to measure coolant temp.
A bad ECT sensor will make the car hard to start.
You should check to see if it is connected and if so then replace it ASAP.
It is located right were the transmission connects to the motor at the very top.

 

well right after the engine swap it was flagging the ect, so after looking I noticed that the wire about an inch from one of the temp sensors was exposed, so I cut and patched it from my old harness with no resolve to the ECU flag, so I tried replacing both temp sensors (1 on the head and the other on the upper return hose) with the ones that were working working on my old motor, but that also didn't have any effect.
EDIT:
I was told that theres 3 temp sensors, but I havn't found the third (kinda doubt there is a third though...) haha
and ran a multi-meter on the wires to verify no signal dedrigation.

 

here is a pic I have from when I did my 5 speed swap.

The sensor with the gray top is the ECT sensor.

It is important that you get that working

 

ok running to the parts store now, thanx

I'll update after I get a chance to test a cold start

 

well since I'm just waiting now... I'm just curious, how would the coolant thermostat affect my start-up/performance/mpg so adversely?

 

because the ECU does not know that the motor is cold so it does not do a RICH MIXTURE which makes a cold car start easier.

Just like how a CHOKE works on a carburetor, a choke makes the mixture richer which allows the motor to start easier when it is cold.

Make sense?