P0638high severityPowertrain
Throttle Actuator Control Range/Performance (Bank 1)
on 1994-2007 Dodge Ram 2500 5.9L I6 Cummins Diesel · 4WD
What this code means
The PCM detected that the throttle actuator is not responding within the expected range. This can cause reduced power and limp mode.
Symptoms
- Reduced engine power
- Check engine light on
- Erratic or limited throttle response
Common causes
- Faulty throttle body/actuator
- Dirty throttle plate
- Damaged throttle control wiring
- Faulty PCM
Diagnostic steps
- Scan throttle position data
- Inspect and clean throttle body
- Test throttle actuator motor and wiring
- Perform throttle relearn or replace throttle body
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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