See the Gristmill blog at http://gristmill.grist.org/story/2008/11/10/72436/290
Please note, for the record, that I did not originate the phrase "Tailpipe Johnny," though I may have been the first to report it in a national magazine in 1982.
The phrase properly should be credited to the late Republican Congressman Ed Madigan of Illinois. The context was Madigan's describing a meeting he had in 1981 with Dingell and then-Republican Congressman Jim Broyhill of North Carolina. Dingell and Broyhill had teamed up to promote legislation, in concert with the Reagan administration, to weaken the Clean Air Act. (This is referenced in the International Encyclopedia of Environmental Politics at http://books.google.com/books?id=hSE9jg_N4-IC&pg=PA91&lpg=PA91&dq=%22dingell-broyhill%22&source=web&ots=ZuzjKddt-L&sig=SGhOyOUXUn4C6YIqUoYN1D8QIeM&hl=en&sa=X&oi=book_result&resnum=5&ct=result )
Madigan recalled that Broyhill and Dingell walked into the room for the meeting. "Here comes Smokestack Jim and Tailpipe Johnny," said Madigan, who later became Secretary of Agriculture under the first President Bush and died of lung cancer in 1994 at the age of 58.