Firebird V8-305 5.0L VIN F FI (1987)
Fluid Pressure Sensor/Switch: Customer Interest
A/T - Buzzing Noise at Idle
Bulletin Number: 93-7-5
Reference Number: 277142
Publish Date:10/92
Subject:
BUZZING NOISE AT IDLE (INSTALL NEW PRESSURE REGULATOR VALVE)
Models Affected:
1984-1993 FIREBIRD MODELS W/4L60 TRANSMISSION
TRANSMISSION APPLICATIONS:
1984-1993 HYDRA-MATIC 4L60 (MD8)
TRANSMISSION TYPE 4L60 700R4
TRANSMISSION MODELS: All
CONDITION:
Some 1984-1993 vehicles equipped with a HYDRA-MATIC 4L60 transmission may have a buzzing noise coming from the transmission when the
vehicle is at idle. The buzzing noise may be noticed more when the vehicle is in reverse at idle.
CAUSE:
The buzzing noise may be a result of pressure regulator valve oscillating due to oil pressure instability at lower idle RPM.