It is highly likely that Rangel calculated that the House would not expel him. The Speaker of the House cannot refuse to sit a representative simply because the individual has committed ethical violations. The Constitution, however, permits expulsion of House members by a 2/3 vote.
Rangel successfully ran for reelection with the ethics charges pending. Rangel probably believed that if he won the election, he could escape the ethics proceedings with a punishment short of expulsion. The committee's recommendation that Rangel face a censure suggests that his gamble worked.
At least a majority of the full House can impose a censure. Now, only the voters in Rangel's district can "fire" him.