check engine light

2004 CHEVROLET EPICA
42,000 MILES • 6 CYL • 2WD • AUTOMATIC
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PROMETHIUS
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my chevy epica will not pass emissions testing due to po171/174 error codes many people have suggested a vacuum leak could be the cause the frame by frame report showed 11.25 hg at the map is this normal
Jun 12, 2011 at 7:58 PM
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WRENCHTECH
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No, that should be up around 16 to 18. It appears to be losing vacuum somewhere.
Jun 12, 2011 at 9:06 PM
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PROMETHIUS
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i have replaced the pcv valve,ihave tested the vacuum with a gauge and read in the green, ihave also sprayed maf sensor cleaner everywhere with no change in rpm,i did a second scan today and the coolant temp read 107.60f identical to the previous scan and i made sure that the engine got up to temperatureanc the coolant was circulating
Jun 12, 2011 at 9:57 PM
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WRENCHTECH
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Sounds like you need some professional help.
Jun 12, 2011 at 10:04 PM