Breakthrough in fatal hit-and-run

Police have made a breakthrough after a Sydney grandmother was killed in a hit-and-run a week before Christmas.

Javaher Rahimi, 66, died in hospital after she was struck by a car at a Guilford intersection in December.

Witnesses incorrectly told police the car involved was a yellow Ford Falcon with black wheels last seen heading west on Hawksview Street.

But NSW Police revealed on Tuesday the car was actually a yellow Mitsubishi as investigators renewed their call for anyone who saw something to come forward.

Ms Rahimi's son was devastated when police answered his mother's phone and informed him of what had happened.

"I tried to ring her phone but nobody answered," Mohammad Rahimi said at the time.

"The third time we rang, the police answered. They came here and they said that unfortunately, my mum had passed away."