请问诸位是什么原因？

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  0"><SPAN style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">您好：</SPAN></P> <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt 10。
    5pt; TEXT-INDENT: -10。5pt; mso-char-indent-count: -1。0"><SPAN lang=EN-US><SPAN style="mso-spacerun: yes">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </SPAN></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">从年限上说，车龄较老，发动机性能较差，应该检查发动机磨损状况，是否已经出现个别气缸的缸压不足，造成燃烧不完全，而出现尾气排放超标，同时应该检查三元催化装置是否已经失效或损坏，也会出现尾气超标，或者气味过大。
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  5pt; mso-char-indent-count: -1。  0"><SPAN lang=EN-US><?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p>&nbsp;</o:p></SPAN></P> <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">希望上述回答能给您帮助</SPAN><SPAN lang=EN-US>,</SPAN><SPAN style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">谢谢！！</SPAN></P> <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-US><o:p>&nbsp;</o:p></SPAN></P> <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">北京市汽车修理公司</SPAN><SPAN lang=EN-US><SPAN style="mso-spacerun: yes">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </SPAN></SPAN><SPAN style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">北京博瑞祥驰汽车销售服务中心</SPAN></P><SPAN style="FONT-SIZE: 10。
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    0pt; mso-fareast-font-family: 宋体; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA">800<SPAN style="mso-spacerun: yes">&nbsp; </SPAN>810<SPAN style="mso-spacerun: yes">&nbsp; </SPAN>1384<SPAN style="mso-spacerun: yes">&nbsp; </SPAN><SPAN style="mso-spacerun: yes">&nbsp;&nbsp;&nbsp;</SPAN><SPAN style="mso-spacerun: yes">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</SPAN>010-82818759</SPAN>。