Exhibit 31.2

I,  David  W.  Whitwell,  certify  that:

1.  I  have  reviewed  this  quarterly  report  on  Form  10-Q  of  Clean Diesel
Technologies  Inc.:

2.  Based  on  my  knowledge,  this report does not contain any untrue statement
of  a  material  fact  or  omit  to  state a material fact necessary to make the
statements  made, in light of the circumstances under which such statements were
made,  not  misleading  with  respect  to  the  period  covered  by this report;

3.  Based  on  my  knowledge,  the  financial  statements,  and  other financial
information included in this report, fairly present in all material respects the
financial  condition,  results of operations and cash flows of the registrant as
of,  and  for,  the  periods  presented  in  this  report;

4.  The  registrant's  other  certifying  officer(s)  and  I are responsible for
establishing  and  maintaining disclosure controls and procedures (as defined in
Exchange  Act  Rules  13a-15  (e)  and  15d-15  (e))  and  internal control over
financial reporting (as defined in Exchange Act Rules 13a-15 (f) and 15d-15 (f))
for  the  registrant  and  have:
     a)   Designed  such  disclosure  controls  and  procedures  or  caused such
          disclosure  controls  and  procedures  to  be  designed  under  our
          supervision  to  ensure  that  material  information  relating  to the
          registrant,  including its consolidated subsidiaries, is made known to
          us  by others within those entities, particularly during the period in
          which  this  report  is  being  prepared;  and
     b)   designed  such  internal  control  over financial reporting, or caused
          such  internal  control  over financial reporting to be designed under
          our  supervision,  to  provide  reasonable  assurance  regarding  the
          reliability  of  financial  reporting and the preparation of financial
          statements for external purposes in accordance with generally accepted
          accounting  principles;
     c)   evaluated  the  effectiveness  of the registrant's disclosure controls
          and  procedures and presented in this report our conclusions about the
          effectiveness of the disclosure controls and procedures, as of the end
          of  the  period  covered  by this report based on such evaluation; and
     d)   disclosed  in  this  report  any  change  in the registrant's internal
          control over financial reporting that occurred during the registrant's
          most  recent fiscal quarter (the registrant's fourth fiscal quarter in
          the  case  of  an  annual  report) that has materially affected, or is
          reasonably  likely  to  materially  affect,  the registrant's internal
          control  over  financial  reporting;  and

5.  The  registrant's  other  certifying  officer(s) and I have disclosed, based
on  our  most recent evaluation of internal control over financial reporting, to
the  registrant's  auditors and the audit committee of the registrant's board of
directors  (or  persons  performing  the  equivalent  functions):
     a)   All  significant deficiencies and material weaknesses in the design or
          operation  of  internal  controls  over financial reporting, which are
          reasonably  likely  to  adversely  affect  the registrant's ability to
          record,  process,  summarize  and  report  financial  information; and
     b)   Any  fraud, whether or not material, that involves management or other
          employees  who  have  a  significant role in the registrant's internal
          control  over  financial  reporting;

Date:  August 11, 2006       By: /s/David W. Whitwell
                                 -----------------------------------
                                 David W. Whitwell
                                 Chief Financial Officer,
                                 Senior Vice President and Treasurer