James, Has the CPR or warm-up regulator been replaced and if so did they check the pressure to see if was to low or to high. Make sure the Idle CO adjustment isn't to rice or lean. This must be done when the car is at normal running temp. Both starvation or running rich can do what your talking about and it can happen anytime. Other things like injectors spray pattern, crimped return fuel line or a reptured rubber hose fuel line can also cause this. There are small filters in the fuel distributor and in the injectors. Something may have been disturbed. Fuel filter with the connector could be a problem if to tight. Fuel pump could be defective even new. John hervey http://www.specialtauto.com/