Hi I'm New here so thanks in advance if a 2003 3ltr s type petrol auto box but problem is u have put it in 4th to start in park and neutral it reverse in drive it seems to go into neutral just can't get drive any help be appreciated thanks

 

First, check the 2 bolts holding the shift cable to the trans are present and snugged up.

Next, check cable adjustment (but may need a new one) and the J-gate mechanism.