[rashawn]

recently i just got my rear motor changed out, now im started to notice that when i come to a complete stop my car idle wants to jump up n down,but not that bad but it sounds like it was to cut off, and at times it will jerk when i am slowing down, i'm thinking it is the catalytic converter but i might be wrong. what else might be the problem















and the check engine light is not on

[JimF]

Check fuel pressure change fuel filter if not the cure it will be a big help.

[Chilly Willy]

It could be the idle air control valve. These are relatively cheap and easy to replace. These can get sticky after a while and can cause the kind of idle speed surge that you're describing.