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EX-10.29

AGENCY AGREEMENT  AMENDMENT                               SEPTEMBER 1, 2003
ECHEMTRADETRADE ENERGY & PETROCHEMICALS LTDA.
             &
ENERTECK CHEMICAL CORP.



                          AMENDMENT TO AGENCY AGREEMENT

                                     BETWEEN

                 ECHEMTRADETRADE ENERGY & PETROCHEMICALS LTDA.

                                       AND

                             ENERTECK CHEMICAL CORP.


This is an AMENDMENT  ("AMENDMENT ") effective  September 1, 2003 to that Agency
Agreement  ("Agreement") which was entered into February 15, 2003 by and between
ECHEMTRADETRADE  ENERGY &  PETROCHEMICALS  LTDA.,  its divisions,  its affiliate
companies  and  concerns,  a  corporation  organized  under the laws of Brazil (
"AGENT ") and the ENERTECK  CHEMICAL  CORP., a corporation  organized  under the
laws of the State of Texas in the United States of America ("EnerTeck").

1.       REPRESENTATION

         The Parties wish to amend and clarify the Agreement as set forth below.

2.       MINIMUM ANNUAL SALES TO MAINTAIN GEOGRAPHIC EXCLUSIVITY

         Appendix "A" of the  Agreement;  Minimum  Annual  Sales for  Geographic
                  Exclusivity shall be and is hereby amended to read as follows:

         Contract Year Ending         Volume of EnerBurn Sold in Territory

         February 15, 2004                           20,000 Gallons
         February 15, 2005                           60,000 Gallons
         February 15, 2006                          100,000 Gallons


3.       TERRITORY


         Appendix "A" of the  Agreement;  TERRITORY  shall be amended to read as
follows:

         BRAZIL
         ARGENTINA
         URUGUAY
         PARAGUAY
         PERU
         CHILE

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4.       COMMISSIONS

         Paragraphthree  of Article 5. of the Agreement shall be amended to read
         as follows:

         "EnerTeck shall pay commissions to Agent on all commercial  accounts in
         Agent's  territory  for as long as this  Agreement is in force and such
         commission  payments  for Active  Accounts  at the time of  termination
         shall continue for five years from the effective date of termination of
         this  Agreement,  regardless of the reason for  termination,  or as the
         Parties may mutually  agree.  An `ACTIVE  ACCOUNT' shall be defined for
         these purposes as any account which has purchased and paid for EnerTeck
         Products within the preceding  twelve-month period,  and/or is actively
         in  negotiations  and/or  discussions  with Agent for the  purchase  of
         Products up to one (1) year prior to the time of termination or loss of
         geographic   exclusivity.   Upon  termination  or  loss  of  geographic
         exclusivity,  Agent  shall  notify  EnerTeck  in  writing of all active
         accounts and it is the  responsibility  of Agent to notify  EnerTeck of
         any changes or additions with respect to Active Accounts.  In the event
         Agent loses  geographic  exclusivity,  EnerTeck  shall protect  Agent's
         proprietary  relationship with Active Accounts and will not arbitrarily
         withhold the  inclusion of additional  Active  Accounts as nominated by
         Agent from time to time."

5.       ACKNOWLEDGEMENT OF "ACTIVE ACCOUNTS"

         EnerTeck hereby  acknowledges and confirms that Agent has been actively
         involved in negotiations  and/or  discussions  with for the purchase of
         Products with the following prospects in the Territory: BR, Vale do Rio
         Doce,  MRS  Logistica,  ALL - Americana  Latina  Logistica,  FCA, 1001,
         Governo do Chile, Mega Petroleo, Ipiiranga,  TransUltra,  TransQuimica.
         Therefore,  all of  those  prospects  shall  be  deemed  to be  "Active
         Accounts"  for the  purpose  of  paragraph  three,  Article  5. of this
         agreement upon termination or loss of geographic exclusivity.


6.       GEOGRAPHIC EXCLUSIVITY FOR BRAZIL

         The Parties  acknowledge  that  Petrobras  (and affiliate BR) are under
         negotiations for an exclusive  sub-distributing contract with Agent for
         the inclusion of EnerBurn in 100% of BR branded  diesel  products.  The
         Parties agree that EnerTeck shall recognize said geographic exclusivity
         in Brazil in the event  that  Agent  loses  geographic  exclusivity  as
         outlined in Article V, where  Petrobras/BR  is  identified as an Active
         Account,  and  Agent  subsequently   contracts  with  Petrobras/BR  for
         Petrobras/BR'  exclusive  distribution of Products in Brazil anytime up
         to one year after termination or loss of geographic exclusivity.

7.       APPENDIX "B" COMMISSION SCHEDULES


FOR ALL GOVERNMENT ACCOUNTS (INCLUDING CHILE, PARAGUAY, BR AND PETROBRAS), Agent
shall be paid a  commission  for  volumes  sold in the amount of the  difference
between (1) the  bulk/Isotank  FOB Houston,  Texas sales price paid to EnerTeck,
and (2) the  commission  basis  price of USD 55.00  per US  gallon  of  EnerBurn
product.


                                                   EXECUTED BY:
ECHEMTRADETRADE ENERGY & PETROCHEMICALS LTDA.      ENERTECK CHEMICAL CORP.



---------------------------------------------      ----------------------------

Francisco CS Gularte                               Dwaine D. Reese
President and CEO                                  Chairman & CEO

DATE:                                              DATE: