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                                                                    EXHIBIT 31.1

                          UAG MENTOR ACQUISITION, LLC.
                  CERTIFICATIONS PURSUANT TO SECTION 302 OF THE
                           SARBANES-OXLEY ACT OF 2002

Certification

I, Roger S. Penske Jr., certify that:

    1. I have reviewed this annual report on Form 10-K of UAG Mentor
Acquisition, LLC;

    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 officers 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)) 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;

      b. 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

      c. Disclosed in this report any change in the registrant's internal
         control over financial reporting that occurred during the registrants
         most recent fiscal quarter that has materially affected, or is
         reasonably likely to materially affect, the registrants' internal
         control over financial reporting; and

    5. The registrant's other certifying officers 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 registrant's board of
directors:

    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
        controls over financial reporting.

                                 /s/ Roger S. Penske, Jr.
                                 -----------------------------------
                                  Roger S. Penske, Jr.
                                  Title: Chairman of the Board
                                  (Principal Executive Officer)

Date: March 30, 2004