The best way that I can describe this is to describe what happens if I'm trying to drive in a straight line down the freeway. Basically, if I'm going 60+ MPH down the freeway, I can feel this sensation that the front end is "wobbling" from left to right. So maintaining straight-line motion requires me to constantly turn left when it feels like its going to the right, and vice-versa. And this is not a pulling to any one direction (as would be the case with a bad alignment)--it randomly alternates in equal magnitude between left and right.

Another thing that I notice--although I don't know if it has anything to do with it--is that the steering wheel is "bouncy". That is, I can be driving a straight line and just randomly rotate the steering wheel an inch or so in either direction from the middle, and the car won't turn at all. When the car is at rest, I can literally "bounce" the steering wheel (i.e. let go after pulling it and it will oscillate).

This is all on a completely rebuilt front end (rebuilt a little more than a year ago). The front end was aligned after the rebuild, and I've not really made any hard-hits into bumps or anything since (beyond the "normal" bumps from the crappy roads here).

Also--I'm not sure if this might be the culprit or not, but--I just went outside, popped the hood, and tried pulling up and down on the idler-arm. It felt a little loose--I could see "steering bar" (the bar that's between the steering box and the idler arm) move on that side. I don't know if a little movement is normal or what, but I did try the same maneuver on the steering box, and it didn't budge.

Any ideas what the problem might be? Is this just what happens when you buy front-end parts from Auto-Zone and I should just buy a new idler-arm?

Thanks

(BTW -- This is on the '88 Camaro SC in the signature.)