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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 HczJ+9d/T/7/LhnS2qeBZc1N7jN/isX64cLQTx290tj7sNGCieDDeu5VVJe6T2DC
 dvCme7hLKcIvsUmqxbQcdQ==

<SEC-DOCUMENT>0001181431-04-026832.txt : 20040519
<SEC-HEADER>0001181431-04-026832.hdr.sgml : 20040519
<ACCEPTANCE-DATETIME>20040519203208
ACCESSION NUMBER:		0001181431-04-026832
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20040517
FILED AS OF DATE:		20040519

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SIMPLOT DON J
		CENTRAL INDEX KEY:			0001202368

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-15143
		FILM NUMBER:		04819947

	BUSINESS ADDRESS:	
		STREET 1:		8000 S. FEDERAL WAY
		CITY:			BOISE
		STATE:			ID
		ZIP:			83707-0006

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			IMPCO TECHNOLOGIES INC
		CENTRAL INDEX KEY:			0000790708
		STANDARD INDUSTRIAL CLASSIFICATION:	MOTOR VEHICLE PARTS & ACCESSORIES [3714]
		IRS NUMBER:				911039211
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		16804 GRIDLEY PLACE
		CITY:			CERRITOS
		STATE:			CA
		ZIP:			90701
		BUSINESS PHONE:		5628606666

	MAIL ADDRESS:	
		STREET 1:		16804 GRIDLEY PL
		CITY:			CERRITOS
		STATE:			CA
		ZIP:			90703

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	AIRSENSORS INC
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>rrd43096.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-05-17</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000790708</issuerCik>
        <issuerName>IMPCO TECHNOLOGIES INC</issuerName>
        <issuerTradingSymbol>IMCO</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001202368</rptOwnerCik>
            <rptOwnerName>SIMPLOT DON J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>16804 GRIDLEY PLACE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CERRITOS</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>90703</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Options</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>5.70</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2004-05-17</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>15000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>5.70</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2014-05-17</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>common stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>15000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>318000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Grant to reporting person of option to buy 15,000 shares of Common Stock exercisable in annual cumulative increments of 25% of total options granted commencing one year from date of grant, subject to earlier vesting based on prior service as a director, upon death, disablement or retirement at or after age 62; all options expire ten years from date of grant.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Don J. Simplot</signatureName>
        <signatureDate>2004-05-19</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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