1997 Mercury Marquis OBD2 codes P0174 & PO171

1997 MERCURY MARQUIS
45,000 MILES • V8 • 2WD • AUTOMATIC
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JACK TIPTON
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Could not smog car because P0174 code. Took it to a mechanic (ford doctor). He replaced the intake Manifold. ( I know the story) Gorman made in China vs Ford intake manifold. He claimed he couldn't get the "O" ring, so a kit from Ford dealer was ordered, which was Ford intake Manifold with Ford gaskets.

I took it back to smog check and it passed. Three times after around 100 or so miles. The check engine comes back on aftwer I erase it with the Equip I bought at Kragens. Now I get P0174 & P0171 to lean bank 1 & bank 2. I would like to know the proper fix before I go back to the Ford Doctor.
Mar 16, 2010 at 2:22 PM
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JACOBANDNICKOLAS
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It sounds like there are more vacuum leaks. Both codes are for a lean mixture which indicates too much air and not enough fuel. Check for broken vacuum hoses or disconnected ones.
Mar 24, 2010 at 8:10 AM