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Daryl, Shop Owner, Master Mechanic
Category: GM
Satisfied Customers: 12549
Experience:  28 years experience, Master Mechanic
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2004 GMC Sierra 1500: maf Sensor, checked fuel pressure 60 psi..hills

Resolved Question:

2004 GMC Sierra 1500 4.8L
got P0171 and P0174 codes, Changed MAF Sensor, checked fuel pressure 60 psi. I still get P0171 and P0174 codes, and lack of power up hills
Submitted: 7 years ago.
Category: GM
Expert:  Daryl replied 7 years ago.
These have a big problem with the intake gaskets leaking and causing the codes and symptoms you are describing. This is a very common problem and replacing the gaskets is the fix for this problem.

Edited by zzdaryl on 1/23/2010 at 8:26 PM EST
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