overheating

Are you driving through town, slow speeds with frequent stopping, or are you driving down the freeway when this seems to happen? It is possible that the cooling fans are not coming on, if they weren't your overheating issue would most likely show up when driving around at slower speeds. If it overheats while going down the freeway the fans probably aren't the issue. Another issue is that it is a "perceived" overheating issue, the temperature sensor is out of range and reporting an engine temperature that is actually hotter the reality. Overheating an engine is a very bad thing, I suggest you get this situation checked out sooner rather than later.