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2001 Audi A4 Quattro Question: code po171

 

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bmorales_09, Hayward, CA, January 27, 2011, 11:57
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i got code po171 system too lean bank 1, i replaced all braded vacum hoses clean maf sensor, change air filter and reset the computer. But after running 30 miles the engine leght came back on. what else is the problem with this? does the o2 sensor got to do something about this?

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  • Answer #1

    schucks from Schucks Transmission, January 27, 2011, 12:19
     Enthusiast

    I RESENTLY HAD A CUSTOMER WITH THIS PROBLEM, CHANGE THE MAF SENSOR AND THIS WAS THE CORRECTION. THIS IS GOING TO FIX THIS PROBLEM 9 OUT OF 10 TIMES. THX JIM

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    Hal..., January 27, 2011, 13:06
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     Master

    Who is this???

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  • Answer #2

    Hal... (see my shops), January 27, 2011, 13:07
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     Master

    Check all the small vacuum lines on the top of the engine again. After 90K they become brittle and will cause the P0171 code. Using a smoke machine usually roots these leaks out but you can use a can of brake cleaner if you have it. Lightly spray around those lines and see if you can get the engine to react. Be cafeful!!!

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  • Answer #3

    Royal Motor Sales from Royal Automotive Group, January 27, 2011, 14:16
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     Technician

    if you have a 1.8L engine it's most likely the hoses under the manifold. I hope that helps.

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    Hal..., January 27, 2011, 14:20
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     Master

    Thank god WorldPac started selling that hose in bulk...

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  • Answer #4

    ccsmog from Contra Costa Smog and Repair, January 27, 2011, 17:31
     Journeyman

    You might also check for manifold leaks.

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