It would be a loss but I think in the long run it would be worth it because
1) Honda Accord is more reliable
2) Honda Accord has better resale value, one of the best in it's class
Car dealers don't give you enough for your trade in's ... so you'd have to sell it privately, sell it on eBaymotors.com or your local newspaper.
If you owe $10,000 on your car loan, someone offers $9,000 for it, you have to pay the $1,000 difference out of your own pocket. Then your car loan is PAIDOFF.
Then go to a Honda dealer and buy a new Accord. Recently they started putting on the "old" 2003 Accords on CLEARANCE, if you buy in the next few months you should be able to score a BRAND NEW 2003 Honda Accord LX for around $16,900 or better.