Exhibit 23.1




CONSENT OF REGISTERED PUBLIC ACCOUNTING FIRM


We consent to the incorporation by reference in the Registration Statements
on Forms S-8  (Registration  Nos.  33-00000,  33-16939 and 33-33276) of our
report  dated  February 18,  2004,  relating to our audit of the  financial
statements of Clean Diesel  Technologies,  Inc. included in the 2003 Annual
Report on Form 10-K.


/s/ Eisner LLP

New York, New York
June 30, 2004