P0121high severityPowertrain
Throttle/Pedal Position Sensor/Switch A Circuit Range/Performance
on 2008 Dodge Viper 8.4L V10 · RWD
What this code means
The TPS signal does not match expected values for the current operating conditions.
Symptoms
- Check Engine Light
- Erratic throttle response
- Stalling
- Hesitation
- Limp mode
Common causes
- Worn TPS
- Carbon buildup on throttle body
- Sticking throttle plate
- Loose throttle cable
Diagnostic steps
- Monitor TPS signal during throttle sweep
- Check for flat spots or dropouts
- Clean throttle body
- Inspect throttle cable/linkage
Repair notes
Clean throttle body. Replace TPS if signal is erratic.
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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