-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 DAWl0v3I6dw7wVIOKGVD2Prx/EpIvGAS4o3umhFJYRR1FSxSoonR/fknaGiADAEn
 P4c5NHmgrSTGrkomKGpoOg==

<SEC-DOCUMENT>0001140361-08-028951.txt : 20081231
<SEC-HEADER>0001140361-08-028951.hdr.sgml : 20081231
<ACCEPTANCE-DATETIME>20081231161020
ACCESSION NUMBER:		0001140361-08-028951
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20081121
FILED AS OF DATE:		20081231
DATE AS OF CHANGE:		20081231

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			RIO VISTA ENERGY PARTNERS LP
		CENTRAL INDEX KEY:			0001260828
		STANDARD INDUSTRIAL CLASSIFICATION:	WHOLESALE-PETROLEUM & PETROLEUM PRODUCTS (NO BULK STATIONS) [5172]
		IRS NUMBER:				200153267
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1313 EAST ALTON GLOOR BLVD.
		STREET 2:		SUITE J
		CITY:			BROWNSVILLE
		STATE:			TX
		ZIP:			78526
		BUSINESS PHONE:		(956) 831-0886

	MAIL ADDRESS:	
		STREET 1:		1313 EAST ALTON GLOOR BLVD.
		STREET 2:		SUITE J
		CITY:			BROWNSVILLE
		STATE:			TX
		ZIP:			78526

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			RICHTER JEROME B
		CENTRAL INDEX KEY:			0001022881

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-50394
		FILM NUMBER:		081279075

	BUSINESS ADDRESS:	
		STREET 1:		26280 DORI LANE
		CITY:			LOS ALTOS HILLS
		STATE:			CA
		ZIP:			94022
		BUSINESS PHONE:		7607729080

	MAIL ADDRESS:	
		STREET 1:		77-530 ENFIELD LANE
		STREET 2:		BLDG. D
		CITY:			PALM DESERT
		STATE:			CA
		ZIP:			92211
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-11-21</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001260828</issuerCik>
        <issuerName>RIO VISTA ENERGY PARTNERS LP</issuerName>
        <issuerTradingSymbol>RVEP</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001022881</rptOwnerCik>
            <rptOwnerName>RICHTER JEROME B</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>335 TOMAHAWK DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PALM DESERT</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92211</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Units</value>
            </securityTitle>
            <transactionDate>
                <value>2008-11-21</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>200</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.1848</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>603722</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Units</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>187</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Spouse</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Jerome B. Richter</signatureName>
        <signatureDate>2008-12-31</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----