ok so when I am stopped or very slow the engine revs a few hundred extra and then back down then again over and over. only happens when in gear if i put it in nuetral then it idels normally .... same with park. feels weird and it happens when the tranny is engaged and pulls you a little bit .... Am still waiting on parts to fix the misfire (magnecor, bosch fusion, fuel filter)

99 DI SD, Auto 75k

 

When was it last tuned, how about a new fuel filter?
First 2 things to do would be clean the t/body and then the IAC, get all the carbon build up out of both of them.