OIL PRESSURE GAGE ERRATIC (REPLACE OIL PRESS. SENSOR)

SUBJECT: OIL PRESSURE GAGE ERRATIC OR DISPLAYS HIGH OIL PRESSURE - REPLACE OIL PRESSURE SENSOR

MODELS/YEARS: 1986-92 TORONADO

Some 1986-92 Toronados may exhibit a condition where the oil pressure gage may be erratic (needle fluctuates) or display very high oil pressures. This is due to an internal intermittent contact within the oil pressure sensor.

To diagnose oil pressure gage complaints check the oil pressure with a mechanical gage using the oil pressure sensor hole in the engine block. The reading you obtain is the measured oil pressure.

- If the measured oil pressure is incorrect according to the engine specifications in Section 6, refer to that section for diagnosis and repair procedures pertaining to high or erratic oil pressure.

- If the measured oil pressure is correct according to the engine specifications in Section 6 of the Service Manual, enter service diagnostics and monitor BCM data parameter BD71. BD71 is oil pressure in psi. BD71 will display a high value with an open or intermittent open sensor and a low value if the BCM oil pressure sensor input is shorted to ground.

- If the BD71 value is steady and agrees with the measured oil pressure, and the intermittent or high instrument panel cluster gage reading is still present, refer to Section BA-82 of the Service Manual for diagnosis of display conditions.

- If the BD71 value is erratic or at maximum value, replace the oil pressure sensor with the appropriate part number listed below.

Model Year Carline P/N --------- ------- --- 1986-90 Toronado 3532954 1991-92 Toronado 25605389

Note: On Toronado with analog (needle) cluster, an open sensor (fixed high BD71 parameter reading) will result in a high gage reading for a few seconds followed by the needle dropping off to approximately zero to 20 psi. On all other clusters and under all other conditions, the cluster display should agree with the BD71 parameter reading.

Parts are currently available from GMSPO.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.