A321 first officer reported fumes during preflight suggesting the APU was likely over serviced.

Attributes
ACN	1632221
Time
Date	201903
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	A321
Operating Under FAR Part	Part 121
Flight Phase	Parked
Flight Plan	IFR
Component
Aircraft Component	APU
Person 1
Function	First Officer Pilot Flying
Qualification	Flight Crew Instrument Flight Crew Air Transport Pilot (ATP) Flight Crew Multiengine
Events
Anomaly	Aircraft Equipment Problem Less Severe Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor

Narrative:

The initial fume event (at the gate) was determined to be the result of an over serviced APU. The aircraft had just come out of a weekly inspection earlier the same day. I suggest mandating a new procedure to insure that APU's aren't over serviced.

Original NASA ASRS Text

Title: A321 First Officer reported fumes during preflight suggesting the APU was likely over serviced.

Narrative: The initial fume event (at the gate) was determined to be the result of an over serviced APU. The aircraft had just come out of a weekly inspection earlier the same day. I suggest mandating a new procedure to insure that APU's aren't over serviced.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.