my 93 accord acts strange at startup, and also vibrates alot when at stoplights. My local supply store had seafoam on sale for $4/can, so I picked one up.

I pulled the hose off the pcv valve, and hovered it about 1/4 inch above the seafoam liquid. This created a swirling tornado effect, slowly inhaling the liquid. The engine reved up and down while I did this.

I did this for about 1/3 of the can, then dunked the hose in the liquid until the car died. The neighbors did not appreciate the smoke show from that :)

I let it sit for about 5 min or so, and then started it up. Then I proceeded to take it out and run it like a raped ape for about 15 min. Took about 5 min for it to stop spewing a white cloud out of the tailpipe.

Upon completion, the car ran noticibly smoother, no vibration at the stoplight, and seemed to have a little more pep. It also idles alot better with less vibration.

Just an idea for any of you whose cars are running rough