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                                                                EXHIBIT 10.147.2

                         Capital One Auto Finance, Inc.
                             3901 N. Dallas Parkway
                               Plano, Texas 75093

                               September 21, 2004

__________________
c/o Onyx Acceptance Corporation
    27051 Towne Center Drive, Suite 100
    Foothill Ranch, California 92610

Dear_____________:

         This letter is to confirm our agreement regarding all of the shares,
$.01 par value per share ("Common Stock") of Onyx Acceptance Corporation, a
Delaware corporation (the "Company"), beneficially owned (within the meaning of
Rule 13d-3 under the Securities Exchange Act of 1934, as amended) by you and any
other shares of Common Stock as to which you may hereafter acquire beneficial
ownership (the "Shares"). In order to induce Capital One Auto Finance, Inc., a
Texas corporation ("Parent"), to enter into an Agreement and Plan of Merger to
be dated as of the date hereof by and among Parent, Foothill Services
Corporation, a Delaware corporation and wholly owned subsidiary of Parent
("Sub"), and the Company (the "Merger Agreement"), you and Parent hereby agree
as follows (capitalized terms used herein but not otherwise defined shall have
the meanings ascribed to them in the Merger Agreement):

         You hereby agree to vote or cause to be voted all of the Shares over
which you have voting power (i) in favor of approval and adoption of the Merger
Agreement, the Merger and the transactions contemplated by the Merger Agreement
and (ii) against any Takeover Proposal involving the Company, and any other
matters which could reasonably be expected to impede, interfere, delay or
adversely affect the Merger and the transactions contemplated by the Merger
Agreement. In furtherance of your voting agreement in this paragraph, you hereby
revoke any and all previous proxies with respect to any of the Shares and grant
to Parent and such individuals or corporations as Parent may designate an
irrevocable proxy to vote all of the Shares owned by you in accordance with this
paragraph on any matters which may be presented to stockholders of the Company
with respect to the matters referred to in (i) and (ii) above in this paragraph.
You hereby acknowledge that the proxy granted by the foregoing is coupled with
an interest and is irrevocable. In addition, you hereby agree to execute such
additional documents as Parent may reasonably request to effectuate its proxy
and voting rights under this paragraph. Notwithstanding anything to the contrary
contained herein, the obligation for you to vote the Shares and the proxy
granted to Parent hereby shall automatically terminate and be of no further
force and effect upon the termination of this letter agreement in accordance
with its terms.

         You hereby agree not to sell or transfer the Shares (except to Parent
or Sub) prior to the Expiration Date.

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         Notwithstanding anything in this Agreement to the contrary, Parent
understands and acknowledges that you will have no obligation as a result of
this Agreement to exercise stock options or other derivative securities
exercisable, exchangeable or convertible into shares of Common Stock.

         You hereby represent and warrant as to the Shares issued, outstanding
and beneficially owned by you as of the date of this letter agreement that,
except as disclosed on Schedule I hereto, (i) you are the sole beneficial owner
of and have full right, power and authority to sell and vote the Shares, or if
you are not the sole beneficial owner, you have the full right, power and
authority to vote the Shares, and in either event, this letter agreement is a
valid and binding agreement, enforceable against you, in accordance with its
terms and (ii) neither the execution of this letter agreement nor the
consummation by you of the transactions contemplated hereby will constitute a
violation of, conflict with or default under, any contract, commitment,
agreement, understanding, arrangement or restriction of any kind to which you
are a party or by which you or the Shares are bound.

         Parent hereby represents and warrants that it has the corporate power
and is duly authorized to enter into this letter agreement.

         We each hereby agree that you are not making any agreement or
understanding herein in any capacity other than in your capacity as a
stockholder of the Company. If you are, or any of your Affiliates, employees or
agents is, an officer or member of the Board of Directors of the Company,
nothing herein shall in any way limit or affect actions taken by you or them in
such capacity, and no action taken in furtherance of your or their fiduciary
duties as an officer or director of the Company shall be deemed to be a breach
of the provisions of this letter agreement.

         We each hereby agree that this letter agreement creates legally binding
commitments, enforceable in accordance with their terms. This letter agreement
(i) constitutes the entire agreement among the parties hereto with respect to
the subject matter hereof and (ii) supersedes all other prior agreements and
understandings, both written and oral, between the parties with respect to the
subject matter hereof. This letter agreement is not intended to confer upon any
other Person any rights or remedies hereunder.

         This letter agreement (and the irrevocable proxy granted hereby) will
terminate, and all rights and obligations of the parties hereto shall terminate,
upon the Expiration Date. "Expiration Date" shall mean the date and the time of
the earlier of (i) the written consent of the parties hereto, (ii) the
termination of the Merger Agreement in accordance with its terms and (iii) the
Effective Time. No such termination shall relieve any party hereto from
liability for any willful breach of this letter agreement occurring prior to the
Expiration Date.

         Each party hereto shall be entitled, without prejudice to the rights
and remedies otherwise available to such party, to specific performance of all
of the other party's obligations hereunder. This letter agreement shall be
governed by and construed in accordance with the internal laws (and not the law
of conflicts) of the State of Delaware. Each of the parties shall pay its own
expenses in connection with the execution and performance of this letter
agreement.
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         If any term, provision, covenant or Arestriction of this letter
agreement is held by a court of competent jurisdiction to be invalid, void or
unenforceable, the remainder of the terms, provisions, covenants and
restrictions of this letter agreement shall remain in full force and effect and
shall in no way be affected, impaired or invalidated.

                           [INTENTIONALLY LEFT BLANK]

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         Please indicate your agreement to the foregoing by signing this letter
agreement in the space provided below, whereupon a binding agreement will have
been formed between us in respect of the foregoing.

                                    Sincerely,

                                    CAPITAL ONE AUTO FINANCE, INC.

                                    By: ________________________________________
                                    Name:  David R. Lawson
                                    Title: President and Chief Executive Officer

Acknowledged and agreed as of the date first written above:

____________________________________________________
_________________________________

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                                   SCHEDULE I

No Exceptions.