Well I'm having 2 seperate but uniquely irritating problems with my 99 right now. First of all, when i'm going straight, i'll have to keep my wheel cocked slightly to the left, and even then the car will go right on it's own and then pull back suddenly. Not anything dramatic but it is definately there. That and the steering feels loose in some places and tight in others, so i'm completely stumped. Also, my idle has been a little off here and there for awhile, mostly too low and sometimes going up and down when i'm coasting in gear. So I replaced the IAC valve, and now my idle is way too high. I tried disconnecting the battery to reset the ECU but it's still off. So any help with these problems would be much appreciated guys.
All I have in this world is my balls and my word, and I don't break 'em for NO ONE.
I am thinking youre rack & pinion steering maybe failing, Have you checked the power steering level, Also have you had youre front suspension also tire pressure should be checked as well & inspected, Also I would take a look at youre motor mounts as well, Sagging or split mounts could cause unbalancement. For you idle problem I would take a look at youre vaccum lines, Also could have a problem with intake manifold gasket problem. Also take a look at tps sensor, I would do a volt test. How long has it been since you have done a tune up?.
Good Luck.
These cars are well known to develop 'Memory Steering', so it could be your front upper strut mounts.