2009 Cadillac Escalade Hybrid – Oil Pressure Drops to Zero With P0521
- Aug 15
- 1 min read
Updated: Aug 15
CUSTOMER CONCERN
Customer states the engine oil-pressure gauge intermittently drops to 0 psi without abnormal engine noise. DTC P0521 is stored.
CAUSE
Mechanical oil-pressure testing remained normal while the scan-tool and dash readings dropped, confirming a failed engine oil-pressure sensor.
CORRECTION
Remove and replace engine oil-pressure sensor and inspect or replace the sender screen beneath it. Clear DTC P0521 and verify stable oil-pressure readings.