<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019d01f2-ece5-76f4-9cc7-3909f38c0e35,g:307c3bb0-73ff-4a67-9c8d-c4de63f56a2b-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:roleRef roleURI="http://powersint.com/role/Cover" xlink:type="simple" xlink:href="psix-20260511.xsd#Cover"/>
  <link:presentationLink xlink:role="http://powersint.com/role/Cover" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_CoverAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentType_019d01f2-ece5-7982-b248-70966c2ed3d1" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentType"/>
    <link:presentationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_DocumentType_019d01f2-ece5-7982-b248-70966c2ed3d1" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentPeriodEndDate_019d01f2-ece5-7bdd-b5f2-2ee8ea6ae4c8" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentPeriodEndDate"/>
    <link:presentationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_DocumentPeriodEndDate_019d01f2-ece5-7bdd-b5f2-2ee8ea6ae4c8" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityRegistrantName_019d01f2-ece5-75d7-baf3-6875358c57bc" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityRegistrantName"/>
    <link:presentationArc order="3" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_EntityRegistrantName_019d01f2-ece5-75d7-baf3-6875358c57bc" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityIncorporationStateCountryCode_019d01f2-ece5-72ba-9e7d-c2b56a1222ee" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityIncorporationStateCountryCode"/>
    <link:presentationArc order="4" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_EntityIncorporationStateCountryCode_019d01f2-ece5-72ba-9e7d-c2b56a1222ee" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFileNumber_019d01f2-ece5-74a2-82a0-a870721f2fb1" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityFileNumber"/>
    <link:presentationArc order="5" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_EntityFileNumber_019d01f2-ece5-74a2-82a0-a870721f2fb1" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityTaxIdentificationNumber_019d01f2-ece5-7b45-bb10-70888112c6df" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityTaxIdentificationNumber"/>
    <link:presentationArc order="6" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_EntityTaxIdentificationNumber_019d01f2-ece5-7b45-bb10-70888112c6df" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine1_019d01f2-ece5-7b08-bc8b-df131a11225d" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressAddressLine1"/>
    <link:presentationArc order="7" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_EntityAddressAddressLine1_019d01f2-ece5-7b08-bc8b-df131a11225d" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown_019d01f2-ece5-76b4-9c6e-c5dbaa19bb6e" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressCityOrTown"/>
    <link:presentationArc order="8" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_EntityAddressCityOrTown_019d01f2-ece5-76b4-9c6e-c5dbaa19bb6e" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressStateOrProvince_019d01f2-ece5-7a7b-a671-740813ab3edc" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressStateOrProvince"/>
    <link:presentationArc order="9" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_EntityAddressStateOrProvince_019d01f2-ece5-7a7b-a671-740813ab3edc" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode_019d01f2-ece5-74a6-b156-e3e16e0d0839" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressPostalZipCode"/>
    <link:presentationArc order="10" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_EntityAddressPostalZipCode_019d01f2-ece5-74a6-b156-e3e16e0d0839" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LocalPhoneNumber_019d01f2-ece5-7d64-ac9b-fa4219598700" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_LocalPhoneNumber"/>
    <link:presentationArc order="11" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_LocalPhoneNumber_019d01f2-ece5-7d64-ac9b-fa4219598700" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CityAreaCode_019d01f2-ece5-7f87-b3e7-285bca00d856" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_CityAreaCode"/>
    <link:presentationArc order="12" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_CityAreaCode_019d01f2-ece5-7f87-b3e7-285bca00d856" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_WrittenCommunications_019d01f2-ece5-75d3-aee1-3de8f51b3ce8" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_WrittenCommunications"/>
    <link:presentationArc order="13" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_WrittenCommunications_019d01f2-ece5-75d3-aee1-3de8f51b3ce8" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SolicitingMaterial_019d01f2-ece5-779f-aec4-9c2ebf302a4b" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_SolicitingMaterial"/>
    <link:presentationArc order="14" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_SolicitingMaterial_019d01f2-ece5-779f-aec4-9c2ebf302a4b" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementTenderOffer_019d01f2-ece5-766b-bd31-848da4d7be02" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_PreCommencementTenderOffer"/>
    <link:presentationArc order="15" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_PreCommencementTenderOffer_019d01f2-ece5-766b-bd31-848da4d7be02" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementIssuerTenderOffer_019d01f2-ece5-7115-b914-862b67c0dba4" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_PreCommencementIssuerTenderOffer"/>
    <link:presentationArc order="16" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_PreCommencementIssuerTenderOffer_019d01f2-ece5-7115-b914-862b67c0dba4" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12bTitle_019d01f2-ece5-7266-b20e-933d40bf4d7f" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_Security12bTitle"/>
    <link:presentationArc order="17" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_Security12bTitle_019d01f2-ece5-7266-b20e-933d40bf4d7f" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_TradingSymbol_019d01f2-ece5-741b-9ae3-4c6e54168c85" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_TradingSymbol"/>
    <link:presentationArc order="18" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_TradingSymbol_019d01f2-ece5-741b-9ae3-4c6e54168c85" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_019d01f2-ece5-74d9-b879-b736dd127885" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_SecurityExchangeName"/>
    <link:presentationArc order="19" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_SecurityExchangeName_019d01f2-ece5-74d9-b879-b736dd127885" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityEmergingGrowthCompany_019d01f2-ece5-7493-9a0b-e446d8cb107c" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityEmergingGrowthCompany"/>
    <link:presentationArc order="20" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_EntityEmergingGrowthCompany_019d01f2-ece5-7493-9a0b-e446d8cb107c" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AmendmentFlag_019d01f2-ece5-701f-8334-e57ec7e36278" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_AmendmentFlag"/>
    <link:presentationArc order="21" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_AmendmentFlag_019d01f2-ece5-701f-8334-e57ec7e36278" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCentralIndexKey_019d01f2-ece5-718f-aff2-016897e652d4" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityCentralIndexKey"/>
    <link:presentationArc order="22" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019d01f2-ece5-7d45-b85e-69bc850e66ec" xlink:to="loc_dei_EntityCentralIndexKey_019d01f2-ece5-718f-aff2-016897e652d4" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
  </link:presentationLink>
</link:linkbase>
