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                                                                   EXHIBIT 3.3.1


                             AMENDMENT TO BYLAWS OF
                               KEY PLASTICS, INC.

         The Board of Directors ("Board") of Key Plastics, Inc., a Michigan
corporation (the "Company"), by unanimous vote at a meeting of the Board on
January 28, 1998, hereby amends the Bylaws of the Company (the "Bylaws"),
pursuant to Article XII of the Bylaws, and in accord with Section 231 of the
Michigan Business Corporation Act, effective February 9, 1998, as follows:

         Sections 5.01, 5.02, 5.03 and 5.07 of the Bylaws is deleted and
replaced in its entirety by the following:

         5.01 NUMBER AND ELECTION. The business and affairs of the corporation
shall be managed by the Board. The Board shall initially consist of five (5)
directors. By August 9, 1998, the size of the Board shall be increased to eight
(8) directors. When the size of the Board is from five (5) to seven (7)
directors, one (1) of the directors shall be appointed by Paribas Principal
Incorporated, a New York corporation ("Paribas") and the remaining directors
shall be elected at each annual meeting of the shareholders, each to hold office
until the next annual meeting of shareholders and until his successor is elected
and qualified, or until his resignation or removal. When the size of the Board
is eight (8) directors, two (2) of the directors shall be appointed by Paribas
and six shall be elected at each annual meeting of the shareholders, each to
hold office until the next annual meeting of shareholders and until his
successor is elected and qualified, or until his resignation or removal. When
the size of the Board is less than eight (8) directors, Paribas shall also be
entitled to appoint one observer who may participate in meetings of the
directors. The directors need not be residents of Michigan or shareholders of
the corporation. Notwithstanding the foregoing, the rights of Paribas set forth
in this Section 5.01 shall terminate as provided in Section 5.13.

         5.02 RESIGNATION AND REMOVAL. Any director can resign by written notice
to the corporation. The resignation is effective upon its receipt by the
corporation or a subsequent time as set forth in the notice of resignation. Any
director elected by the shareholders, or all the directors elected by the
shareholders (but not the directors appointed by Paribas) may be removed, with
or without cause, by vote of the holders of a majority of the shares entitled to
vote at an election of directors. Any director appointed by Paribas, or all the
directors appointed by Paribas (but not the directors elected by the
shareholders) may be removed, with or without cause, by Paribas. Notwithstanding
the foregoing, the rights of Paribas set forth in this Section 5.02 shall
terminate as provided in Section 5.13.

         5.03 VACANCIES. Vacancies in the Board of directors eligible for
election by the shareholders occurring by reason of death, resignation, removal,
increase in the number of directors or otherwise shall be filled by the
affirmative vote of a majority of the remaining directors that were elected by
the shareholders, though less than a quorum of the Board, unless filled by
proper action of the shareholders of the corporation. Each person so elected
shall be a


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director for a term of office continuing only until the next election of
directors by the shareholders. Vacancies on the Board of the directors eligible
for appointment by Paribas by reason of death, resignation, removal, increase in
the number of directors or otherwise shall be filled by proper action by
Paribas. Notwithstanding the foregoing, the rights of Paribas set forth in this
Section 5.03 shall terminate as provided in Section 5.13.

         5.07 QUORUM. The number of directors required to constitute a quorum
for the transaction of business shall vary depending upon the size of the Board
as follows:

                  Size of Board               Number Required for Quorum
                -----------------             --------------------------
                     5                                  3
                     6                                  4
                     7                                  4
                     8                                  5

A majority of the members of a committee of the Board constitutes a quorum for
the transaction of business of the committee. Approval by the Board shall
require a majority of the Board, and not just a majority of the quorum, except
as a larger vote may be required by the laws of the State of Michigan. The vote
of a majority of the directors present at any meeting of a committee at which
there is a quorum shall be the acts of the committee, except as a larger vote
may be required by the laws of the State of Michigan. A member of the Board or
of a committee designated by the Board may participate in a meeting by means of
conference telephone or similar communications equipment by means of which all
persons participating in the meeting can hear each other. Participation in a
meeting in this manner constitutes presence in person at the meeting.
Notwithstanding the foregoing, the rights of Paribas set forth in this Section
5.07 shall terminate as provided in Section 5.13.

         Section 5.08 of the Bylaws are amended by adding the following sentence
at the end of said section:

         The Board shall cause a director appointed by Paribas to be on each
material committee of the corporation and on each governing board or each
material committee of each subsidiary of the corporation except for Materias
Plasticas S.A. Notwithstanding the foregoing, the rights of Paribas set forth in
this Section 5.08 shall terminate as provided in Section 5.13.

         Article V of the Bylaws are amended by adding at the end of such
Article, the following Sections 5.11 and 5.12:

         5.11 LIMITATION ON POWERS. (a) Subject to the provisions of Section
5.13, notwithstanding any other provision set forth in this Article V or any
other provision contained in these Bylaws to the contrary, no agreement of
merger of the corporation may be adopted by the Board except with the approval
of at least 90% of the Board then in office.

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         (b) Subject to the provisions of Section 5.13, notwithstanding any
other provision set forth in this Article V or any other provision contained in
these Bylaws to the contrary, except with the approval of at least 90% of the
Board, no act shall be taken, sum expended, decision made, obligation incurred
or power exercised by the Board on behalf of the corporation, and the Board
shall cause each of its subsidiaries to abstain from acting with respect to the
following:

         (i)      incur indebtedness unless the incurrence of such indebtedness
                  would be permitted under the Indenture Agreement dated March
                  24, 1997, entered into by the corporation, several affiliates
                  of the corporation and Marine Midland Bank, as amended (the
                  "Indenture"), as in effect on February 9, 1998 and whether any
                  amounts remain outstanding thereunder, and any less
                  restrictive amendments thereto;

         (ii)     the sale or other disposition of any type, in a single
                  transaction or series of related transactions, of assets, the
                  gross proceeds from any such sale which exceeds $15,000,000,
                  or the sale or other disposition of assets, the gross proceeds
                  from all such sales occurring after February 9, 1998 which
                  exceeds $30,000,000, in the aggregate;

         (iii)    capital expenditures in any fiscal year in excess of 125% of
                  such year's budget as approved by the Board;

         (iv)     enter or permit any of its subsidiaries to enter into any
                  business other than Permitted Business (as defined in the
                  Indenture as in effect on February 9, 1998);

         (v)      all other mergers, acquisitions (of stock, assets or
                  otherwise), partnerships, joint ventures, purchases of assets
                  and similar transactions, in excess of $75 million
                  individually or $150 million in the aggregate beginning on
                  February 9, 1998, provided, however, that this restriction
                  shall not apply to such a transaction that results in a sale
                  of substantially all of the assets of the corporation;

         (vi)     amendments to the Articles of Incorporation of the
                  corporation;

         (vii)    file for bankruptcy or other liquidation, winding up or
                  dissolutions events; and

         (viii)   the issuance of equity of the Company, except for the
                  following:

                  (a)      the amount received for such offered interest is, on
                           a proportionate basis, equal to or in excess of 110%
                           of the amount paid by Paribas for its member interest
                           in Key Plastics Technology, L.L.C., a Michigan
                           limited liability company ("Technology"), or, if such
                           equity interest is issued prior to January 31, 1999,
                           unless the amount received is at least equal to the
                           amount paid by Paribas, or

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                  (b)      an issuance of equity to use as consideration in an
                           acquisition of a business or assets or a joint
                           venture or similar transaction approved by the Board.

         5.12 VOTE AS MEMBER OF TECHNOLOGY. Notwithstanding any other provision
set forth in this Article V or any other provision contained in these Bylaws to
the contrary, whenever any action is required by the corporation as a member of
Technology, such action shall be taken by a majority of the shareholders of the
corporation voting in accordance with their equity ownership of the corporation.

         5.13 TERMINATION OF CERTAIN PROVISIONS. Upon the occurrence of a
Qualified Public Offering, as defined in the Equityholders Agreement between the
Company, Technology, Paribas and certain shareholders of the Company, dated
February 9, 1998 (the "Equityholders Agreement"), all vote requirements of
greater than 50% contained in these Bylaws including, without limitation, those
contained in Sections 5.11 and 12.01 shall terminate. In addition, at such time
that Paribas' interest in Technology is equal or below 15%, Paribas shall be
entitled to appoint only one (1) director under Section 5.01 hereof and at such
time as Paribas' interest in Technology is equal or below 5%, Paribas is not
entitled to appoint any director under Section 5.01 hereof.

         Article XII of the Bylaws is deleted and replaced in its entirety by
the following:

                                   ARTICLE XII
                                   AMENDMENTS

         12.01 AMENDMENTS. The Bylaws of the corporation may be amended, altered
or repealed, in whole or in part, by the shareholders or by the Board of
Directors at any meeting duly held in accordance with these Bylaws, provided
that notice of the meeting includes notice of the proposed amendment,
alternation or repeal, provided, however, that: (i) subject to the provisions of
Section 5.13, Sections 5.01, 5.02, 5.03, 5.07, 5.11 or the last sentence of
Section 5.08 may not be amended, altered or repealed, in whole or in part,
without the approval of at least 90% of the Board and (ii) notwithstanding any
other provision set forth in this Article XII or any other provision contained
in these Bylaws to the contrary, Section 5.12 may not be amended, altered or
repealed, in whole or in part, without the approval of majority of the
shareholders of the corporation voting in accordance with their equity ownership
of the corporation.




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