Need suggestion for clearing the code P0172 I have exhausted known solutions

Question

changed fuel cap, checked and gapped plugs at 40, changed air filter (was using K&N put paper element in ) cleaned old MAF and bought new MAF sensor, changed 02 sensor bank 1 upstream. Had fuel pressure checked and was told that it is reading fine.

Answer 1

P0172 Fuel trim rich

Rich fuel trim is mostly a mechanical condition such as low compression, and this would be a major repair, There are still another area that you have to rule out such as the fuel pressure regulator, if its vacuum connection leaks fuel it will cause a rich running condition, There is also the EVAP canister if that is saturated with raw fuel that will cause a rich running condition

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Here the fuel pressure regulator pulls the vacuum hose if fuel seeps out replace the fuel pressure regulator.