[cpayne5]

There's no reason to replace them all at the same time, unless it makes you feel good, I guess. What model and engine? It probably has either 4 or 6 coil packs, depending on the engine.

It shouldn't take any more than 20 minutes (less for most cars) to replace a single coil pack. Add 2 minutes for each additional coil pack . In the aftermarket, you can pick up a coil pack for ~$50-75 for this era Nissan. A good, independent shop should be able to replace a single coil pack for under $100. If you have a 10mm wrench, you can replace it yourself.