Thanks Ruf! I'm wondering if this could be the trouble with my car. Here's what's been going on:
The car seems to idle fine most of the time, but breaks up pretty bad through the rpm band. If I'm very, very smooth with the gas it will tach up normally. I just replaced the plugs and the ignition wires. I did notice that one of the plugs (number three cylinder, I think) had oil all over it. What order do the cylinders go, btw? I took it to Autozone and the code was: Cylinder four misfire P0304. The plug with the oil on it was, looking down at the engine from the front of the car, third from left to right, so it couldn't be number four.
I did a visual inspection of the vacuum lines. They look ok, but who knows. Could it be the EGR valve?
Could it be a throttle position sensor?
Thank you in advance!