P0172 & P0175… I got questions!

[FigureItOut]

2015 Tahoe LT 113k
Codes P0172 & P0175 Too rich bank 1&2
Fuel in oil, just started dieseling on shut off after idling. MAF clean, air filter and intake hoses good. Could it be the O2 sensors, injectors? I do not have any fancy diagnostics (just a basic code reader) leaning towards a bad HPFP. Thoughts, suggestions? I would have to replace this myself and I got questions. Do not want to dive into that without a bit of knowledge from forum friends.
Thanks! (Yes, I changed the oil immediately

 

[LsHart]

Sounds like ur on the right track. Possible evap solenoid stuck open.

 

[jaxscuby]

similar thing happened to coworkers 16 silverado..my basic code reader detected P0172. truck smelled of fuel at idle.
no mis-fire codes..

had a shop use their scanner and found one of the injectors malfunctioning, almost stuck open.

suggest you get the code scanned before you part throwing parts at it.

 

[Doubeleive]

Primary causes,

1. High-Pressure Fuel Pump (HPFP) Internal Leak. #1 cause high pressure fuel pump failure​

• The Mechanism: These engines have two fuel pumps. The high-pressure pump is located under the intake manifold and is driven by the camshaft. If the internal seal on the pump plunger fails, high-pressure fuel leaks directly into the lifter valley and drains into the oil pan.
• Symptoms: Rapidly rising oil level on the dipstick, strong smell of gas in the oil, and sometimes a "P0172" or "P0175" (System Rich) trouble code.

2. Leaking/Stuck Fuel Injector​

Because the injectors in this engine spray directly into the combustion chamber at up to 2,000+ PSI, a failure can dump a lot of fuel.

• The Mechanism: If an injector tip is worn or stuck open, it continues to drip fuel into the cylinder after the engine is shut off. This fuel washes past the piston rings (cylinder wash) and enters the crankcase.
• Symptoms: Hard starting (long crank), rough idle upon startup, and blue/white smoke from the exhaust.