Can I amend my Detroit city tax return after e-filing?

[KrisD]

Yes, but in the TurboTax programs, the local returns are embedded in the state returns. 

You would need to amend the Michigan return, print, and mail only the Detroit return, if that is the only one you need to change. 

All amended returns need to be mailed, they cannot be e-filed.

https://ttlc.intuit.com/replies/3288565