hi all. My 2001 Lumina seems to be shaking a little bit at idle, and sometimes stumbles on light accelleration. My question is, What should be done as maintence? it only has 50,000 miles on it, and the plugs and wires look good. Not cracked or anything. I was planning to do the fuel filter here soon. That just irks me that it idles that way, I mean, it seems nomal to me, thats how it has always idled, one person said that their alero doesnt idle funny like that. I know its got the 3.4 in it, but I've ridden in it, and it doesnt shake like mine when it idles. Whats funny is that it sometimes doesnt idle wierd. seems to more often when warmed up, and sometimes it will be idleing smooth and then a little tiny miss and normal again. I have also read forums of peoples luminas idleing down to 500rpm's. I find this strange, cause mine only idles down to about 800 with no accesseries running. Once again, this is a very small shake while idleing, but is noticable. its done it as long as i can remember, I was just wondering if its normal, and if my car should idle down to 5-600 rpm's. Any info would be greatly appreciated. Thanks