Code p0171, vacuum diagram needed

2003 PONTIAC GRAND AM
167,000 MILES • 3.4L • V6 • 2WD • AUTOMATIC
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SBMISRY
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I'm getting a p0171 code, new intake manifold gasket, wires and iridium plugs are new. Going to order all vacuum hoses from Rock Auto. PCV valve, PCV hose, PCV grommet, mass airflow sensor, vacuum hose, vacuum harness. Also need a vacuum diagram. please.
Feb 18, 2021 at 10:53 PM
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DANNY L
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Hello, I'm Danny.

Here is the diagram you requested. I've attached below diagnostic steps relating to code P0171 as well as the emission hose routing diagram for your car. Hope this helps and thanks for using 2CarPros.
Feb 19, 2021 at 1:26 AM
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Okay, I replaced all vacuum hoses, new PCV valve. I cleared the code. I noticed it had more power and shifted a little harder. I'm guessing the computer needs to adjust. Then the came back on. I do have a brake in the exhaust. It's where the resonator pipe connects to the pipe coming out of the catalytic converter. Could this be the lean fuel in bank ¹?
Feb 23, 2021 at 1:42 AM
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ASEMASTER6371
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Good morning,

I would test the fuel pressure. You may have low fuel pressure from a weak fuel pump.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

https://www.2carpros.com/articles/how-to-replace-an-electric-fuel-pump

Roy
Feb 26, 2021 at 8:42 AM
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DANNY L
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Hello again.

Can you take a picture of where the exhaust leak is with your cell phone and upload it here? Depending where the leak is it might be giving your downstream oxygen sensor a false reading due to leakage. That could be giving a lean code. I would definitely have the leak fixed. I've attached a picture below of the downstream oxygen sensor. Hope this help and thanks again for using 2CarPros.

Danny-
Feb 27, 2021 at 5:52 PM
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I used exhaust cement. that stuff got everywhere because it was so sticky. But it doesn't leak. I cleaned the MAF sensor and no more codes. Idles and runs great.
Feb 27, 2021 at 6:37 PM
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DANNY L
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Glad to hear!
Thanks again for using 2CarPros and we hope you will use our site again in the future when needed.

Danny-
Feb 27, 2021 at 6:49 PM