When I go to watch City play I park in Rondin Road which is a little bit less than one mile south of the Stadium.
I have parked there since City moved to the stadium and have never had any problems. No charges.
Tales about 15 minutes to get to the stadium via
Right – Ashton Old Road – walk approx 300 metres then left – Rylance Street.
Walk to end then right and first left into Darley Street – walk to the end (Ashton New Road) and you will see The Etihad in front of you.
Note that I travel from the South so this works for me. I used it when I was staying in Oldham last year and it did take a little while to get back.
HTH