We have had this car for nearly ten years and never had any major problems until we happened to get an oil change while at Wal Mart and they managed to drop something in the engine while doing it. When we drove the car from the store it started to make a clinking sound. When we went back they told us to prove it! So we took it to a mechanic who said it would be simply cheaper to replace the engine than to fight over it. Well he ended up putting the engine in wrong and it died out and needed another one. It becomes an even sadder story from there. The car still runs but it just isn't the same. It currently sits at 176,000 miles.
I have one with the 3800 which has a lot of pickup. Most people think the car is pretty lame until you hit the gas and turn up the stereo. The stereo on the car is unbelievable for stock. I also love the quad exhaust and spoiler that just hint at the little secrets this car hides!
I don't think this car needs many improvements. It is a basic car with a little kick. I would buy another Lumina if I could to replace this one but they are aging cars and hard to find under 100,000 miles but if you do find one, buy it while you still can.