car comes up to normal temp, but when driven, the temp falls to below the cold r on 1993 Infiniti G20

warm air comes out during idling, but not when driven

Asked by for the 1993 Infiniti G20
replace the thermostat.

did that
what temp thermostat??
do not know, it was the only one autozone had
has to be 195.

1 more answer
This is an old post but make sure you get the same temp thermostat when replacing, i put wrong one in once and engine computer in oldsmobile did not function right.