328 hard to start with cold engine (not cold weather)

If the 328 sits for a day or more, especially a week, it starts very rough. It cranks and starts but it will die as I start to push on the gas pedal. The second try it will start and come to life as I push on the pedal more but it is rough for a few seconds. Then, the engine is normal while warming up and when driving. It also starts fine while the engine is warm.

This began occurring after the car was serviced (changed coolant, oil and replaced right radiator fan relay) but it may be unrelated to it. Also, The battery is only a few months old and it cranks fine. I never had to push on the pedal before to get it to start, only to get the battery/alternator light to go out. With fuel injection, I should not have to push on the pedal.

I looked through the archives and did some other research. So far, this is what directions that takes me:

1. Coolant temperature sensor -- disconnected it and cleaned contacts
2. Frequency/metering valve -- cleaned contacts and verified it is vibrating and the fuel pump is running
3. Aux air valve
4. Cold start injector -- cleaned contacts
5. Thermo time switch
6. Fuel pump pressure relief valve
7. Fuel injection delivery pump starting relay

It seems like a fuel problem where the fuel pressure is decreasing with time or the coolant temp sensor is not getting the signal to the cold start injector to put fuel in. I was thinking of trying to see if voltage is getting to the injector plug.

Thanks for any help.