Imposing term limits on Congress might actually make it more corrupt.
It would backfire. Politics would become more partisan - and possibly more corrupt - due to stronger, more influential political party machines.
Look at Mexico for what would happen. Instead of being able to keep their jobs as longtime incumbents, Mexican politicians are forced out of their offices. But here's where the unintended consequence begins: the term limited politician wants a new job (e.g. a senate seat or governorship after serving in the house). To get their next political position, they need the party's help. to get the party's help they do things the party wants them to do, that they otherwise wouldn't. This is the classic definition of power.
Longtime incumbents are often the most moderate and willing to compromise. Think about Mark Hatfield, Thad Cochran, Joe Biden, Carl Levin, Robert Byrd, Russell Long... They've seen so much, and their incumbency means they rely less on their base and/or party to get reelected.
California tried out term limits, and it ended horribly for them.
To launch a political career, one must simply win a primary election. Primary campaigns in each party have become the new battleground between interest groups, which can get more for their dollars because the electorate is smaller. Freshly minted legislators often feel they owe their careers to whichever interest group funded their first successful race.