You can reset adaptation back to Mean Base Line by re-setting/re-activating the ECU memory . After you have cleared all existing codes [Single flash verification ], you then hold button for 6-8 secs. after the single flash. [wait 2 secs after single flash].. Turn off key for 2 secs, On for 10 and then start.
This is NOT a code clear, it is ECU memory reset. That gets your ECU back to Normal . From there the unit will adapt to the new parts and sensors, but rather then coming back from high adaptation extremes, it will come up/down, +/- as required from a Normal Base value.
The ECU can/will readapt from the old memory by itself with drive cycles [ relearn process] , but if the trims were way out , you can still get codes coming back while the process takes place..so, it is easier to just clear/reset the memory after you have changed parts and have cleared the diagnostic codes ..you are then assured of starting with an ECU that has a Mean Base Line setting value..[ ie..a Normal setting]..which should be closer to proper adaptations with the new remedy parts.
Just a short-cut........

Also, as SB mentions..FP regulator leaking diapragm will supply the engine with unmetered raw gas..not only will the engine suck raw, un-metered gas into the intake from engine vac , but the Fuel Pressure will go higher than spec and compound that problem...that would be a first check..
the same can be a vac leak..a vac leak of unmetered air is read by 02 as a lean condition , so th ECU tries to enrichen this false reading, resulting in wrong A/F mix..
Both reg and vac leaks will force trim levels +/- that it may not be able to handle [ beyond limit].........and result in crap MPG/Running condition.
If one does find a leaking/bad FP reg, it is also a good idea to change the oil.

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A Dalton