After replacing radiator it stalls when you put it in gear

Hi and thanks for using 2CarPros.com.

I have a feeling there is an air leak somewhere which resulted from taking things apart to replace the radiator. Take a look through this link. It discusses reasons why an engine will stall at idle.

https://www.2carpros.com/articles/stall-at-idle

Let me know if anything there helps or if you have additional questions.

Take care,
Joe