Sounds like a vacum leak. Check all the hoses especially the two larger ones that go to the air intake. If you replace the hoses, check for orifices in the hoses and transfer them to the new hose.
Could also be a bad temperature sensor, does the engine run ok once it warms up?
Check your service manual for the fuel section troubleshooting pointers.
Hope it helps,
PS Welcome to the group.
Rick and Cathy from Sarnia, Ontario, Canada
88 LeSharo 2.2L gas auto
We drive in 'NANAZBUS'.
Our grandchildren love it.