Code P0172

2009 CHEVROLET HHR
198,000 MILES • 2.2L • 4 CYL • 2WD • AUTOMATIC
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LALMEN21
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Got a system too rich bank 1 code. I changed the spark plugs and coil packs, changed the mass air flow sensor, changed MAP sensor, changed the 2 oxygen sensors, changed the fuel injectors, cleaned the throttle body. It still stutters and stalls out. I don't know how to perfectly do a vacuum leak test but I'm not even sure that's the problem, hence why I'm posting. Can you point me in the right direction?
Aug 29, 2021 at 6:25 PM
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JACOBANDNICKOLAS
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Hi,

Based on that code, you are getting too much fuel to the engine. In this case, it wouldn't be a vacuum leak. A vacuum leak would allow unmetered air to enter the engine and create a lean mixture. This code can be caused by several things. However, here is a link that shows how to test for a vacuum leak:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Have you checked fuel pressure? Is this the only code present? If you have a live data scan tool, could you let me know the short-term fuel trims?

Make sure there are no restrictions in the air intake tube/air filter box. Also, check fuel pressure. Here is a link that shows how it's done:

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

I attached the manufacturer's pressure specifications below. Do this and let me know what you find.

Take care,

Joe

See pic below.
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Aug 30, 2021 at 7:20 PM