P0521 on Buick vehicles The oil pressure sensor reading does not track what the engine is doing

A model year is listed because the code is named in its own record — a bulletin filed against it, or an owner’s complaint about it — not because every one of these vehicles sets it. Counts are documents in NHTSA’s files, not failure rates.

Owners’ own words, scrubbed of anything identifying. Unverified reports filed with NHTSA — what was said, not a finding that it was true.

Bulletins and campaigns Buick filed with NHTSA whose summary names P0521. Quote the document number at the service desk — it is a diagnosis the maker has already written down.

• A202302140 Service bulletin
  2020-04-14 · Fuel System, Gasoline
• Service Update Bulletin. On certain vehicles, the engine oil pump may be stuck due to foreign material, and diagnostic trouble codes (DTC) P0521, P06DE, P06DD could be set. Dealers are to perform the engine oil pump screening test.
• A202302140 01 Service bulletin
  2020-06-04 · Engine
• Service Update - On certain vehicles, the engine oil pump may be stuck due to foreign material, and diagnostic trouble codes (DTC) P0521, P06DE, P06DD could be set. Dealers are to perform the engine oil pump screening test and if necessary, replace the oil pump.
• PIP5826 Service bulletin
  2021-11-08 · Engine
• This Preliminary information communicates to the dealers information related to isolating a potential engine wiring harness issue causing a MIL on with P0521.
• PIP5826A Service bulletin
  2021-11-09 · Engine
• This Preliminary information communicates to the dealers information related to isolating a potential engine wiring harness issue causing a MIL on with P0521.
• PIP5826B Service bulletin
  2021-12-22 · Engine
• This Preliminary information communicates to the dealers information related to isolating a potential engine wiring harness issue causing a MIL on with P0521.
• PIP5932C Service bulletin
  2024-08-13 · Electrical System
• This Preliminary information communicates to dealers engine wiring harness inspections and engine oil pump diagnostic testing related to MIL on with P0521.
• PIP5932D Service bulletin
  2024-08-13 · Electrical System
• This Preliminary information communicates to dealers engine wiring harness inspections and engine oil pump diagnostic testing related to MIL on with P0521, P06DD or P06DE.
• PIP5947B Service bulletin
  2024-08-16 · Engine
• This Preliminary information communicates to the dealers information related to potential failed engine camshaft cover causing excessive engine oil consumption and blue smoke from the exhaust system at low mileage. Can also possibly cause a misfire and may or may not set history or current codes P0300 P050D P0521 P06DE. It advises inspections for potential engine camshaft cover replacement.
• PIP5947C Service bulletin
  2024-12-05 · Engine
• This Preliminary information communicates to the dealers information related to potential failed engine camshaft cover causing excessive engine oil consumption, blue smoke from the exhaust system at low mileage. Can also possibly cause a misfire or idle surge and may or may not set history or current codes P0300 P050D P0521 P06DE P1101. It advises inspections for potential engine camshaft cover re
• A222379710 Service bulletin
  2022-12-13 · Engine And Engine Cooling
• Service Update. In certain vehicles, if the Engine Control Module (ECM) sets the DTC P0521 (Engine Oil Pressure Sensor Performance), the ECM cannot clear the permanent status of this DTC. If the ECM had previously set a DTC P0521 and the permanent status is not properly cleared, the vehicle may not pass certain Emissions Inspection/Maintenance (I/M) tests. Dealers are to reprogram the ECM.
• A222379711 Service bulletin
  2024-03-14 · Engine And Engine Cooling — Exhaust System — Emission Control
• Emission Recall. General Motors has decided to conduct a Voluntary Emission Recall involving certain vehicles. The Engine Control Module (ECM) may not clear the permanent status of DTC P0521 (Engine Oil Pressure Sensor Performance). If the ECM had previously set a DTC P0521 and the permanent status is not properly cleared, the vehicle may not pass certain Emissions Inspection/Maintenance (I/M)
• PIP4786C Service bulletin
  2016-08-15 · Engine And Engine Cooling
• THIS PRELIMINARY INFORMATION COMMUNICATION PROVIDES INFORMATION TO THE TECHNICIAN ABOUT VEHICLES THAT MAY HAVE LOW OIL PRESSURE MESSAGE. TECHNICIAN MAY ALSO FIND A DIAGNOSTIC TROUBLE CODE P0521 IN THE ENGINE CONTROL MODULE. TECHNICIAN SHOULD FOLLOW ALL PUBLISHED SERVICE INFORMATION DIAGNOSIS. WHEN USING A SCAN TOOL IF THE OIL PRESSURE IS LOW BUT THE OIL PRESSURE AT THE OIL FILTER HOUSING IS CORREC

A stored code names the test that failed, never the part that caused it. The record above is what Buick and its owners have filed about it; the code’s page across every make has the whole file.