What causes the 2007 honda accord vsa and check engine light to come on?

If both the vehicle stability assist (VSA) and check engine light (CEL) come on simultaneously on Your 2007 Honda Accord, it basically means that the onboard computer has detected a fault with the portion of the system that ensures stability for Your vehicle. At least, that's theory. The reality is You probably have a loose gas cap. No, really. If You've taken a curve too fast, You can see this happen. The VSA indicates that there was wheel slippage or one of the wheels is turning faster than the other. When You turn, the difference between the two tires increase, which can result in spinning tires. The VSA tries to keep Your tires from constantly spinning to conserve fuel (which is why a loose gas cap can also trigger this error) and gets confused by fast cornering (since it's unlike typical highway driving.) There's another fun possibility, and that's that Your engine is mIS Firing. This is so common in Hondas with V6 engines that there was A-A-Classction lawsuit that resulted in Honda paying for all the repairs necessary to correct it!