They have not the standing to sue, nor the balls to impeach.
Not content to have wrested from their lackeys on the Supreme Court the right to exclude from Medicaid millions of low income citizens of Repugnant governed states, the punks infesting the lower house of congress writhe in continued agony over their impotence.
They promise, therefor, continued frivolous lawsuits, such as the one presently in train purporting to object to the extension of federal subsidies to low income consumers seeking coverage on the (fallback) federal exchange, Healthcare.gov.
One may anticipate an entertaining bit of contortionist artistry as an utter stranger to the transaction attempts to insert himself in order to be heard to object to the terms pursuant to which one party, the IRS, extends to a second party, the taxpayer, a cash transfer payable to a third party, an insurer.
Lotsa luck, chump. (Parenthetically, the New York Times manages two pages on the topic without guiding the reader to the lack of standing afflicting the prospective litigants.)
More entertaining still, a hearing proposed by the House entitled: "The President’s Constitutional Duty to Faithfully Execute the Laws, will be presided over by Robert Goodlatte, a teabagger of tiny brain and smaller dick.
Here's a hint, nimrod. If you think you have a beef over a failure to enforce, you need to bring on impeachment. Othewise, shut the fuck up.