Hey guys,

I got into my 03 sedan and drove to a restaurant 10 miles away. After I ate I got back in like an hour later started her back up and it felt like the car was misfiring. I watched the idle dip below 600 and almost stall but it caught itself before it got too low. Then shortly after the dip I heard the right side of my motor knocking/rattle at idle. It continued to make this knocking sound off and on all the way home (20miles away). When I got home I popped the hood while it was idling and I could not hear the noise any more. I then place my hand on the motor and it felt like it was shaking slightly. This is not the first time I have heard these noises or had the car to almost stall though but I am not sure what may be causing this issue. I recently changed the oil (600 miles ago) and I alway use 93 octane fuel. The only thing that I can think of is that somewhere around my plenum spacer (only mod on my car) I may have a vacuum leak. Does anyone else have any other ideas, help, advice.?

Thanks.