P0991moderate severityPowertrain
Transmission Fluid Pressure Sensor/Switch F Circuit Intermittent/Erratic
on 1997 Ford Probe 2.5L V6 · FWD
What this code means
The signal from transmission fluid pressure sensor F is dropping out or jumping around instead of staying steady. This usually points to a loose connection or a failing sensor.
Symptoms
- Erratic or harsh shifting
- Transmission warning light on
- Intermittent limp mode
Common causes
- Loose or corroded sensor connector
- Damaged sensor wiring
- Faulty pressure sensor F
- Low or contaminated transmission fluid
Diagnostic steps
- Scan for stored and pending codes
- Inspect sensor connector and wiring while wiggling
- Monitor pressure sensor data during a test drive
- Replace sensor if signal drops out under known-good wiring
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Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0005
Fuel Shutoff Valve A Control Circuit/Open
P0006
Fuel Shutoff Valve A Control Circuit Low
P0007
Fuel Shutoff Valve A Control Circuit High
P0008
Engine Position System Performance - Bank 1
P0009
Engine Position System Performance - Bank 2
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1