P0639

Symptoms

• The engine has entered limp mode.
• Vibration and rough engine operation
• Check Engine light comes on
• Power reduction
• Rough idle

Causes

• Bank 2 throttle valve is dirty or mechanically stuck
• Bank 2 Throttle Position Sensor (TPS) malfunction
• Bank 2 throttle actuator motor malfunction
• Damage to the wiring or connectors of the bank 2 circuit
• ECU malfunction

How to Fix

1. Check and compare Bank 1 and Bank 2 TPS data on scanner
2. Clean bank 2 throttle body
3. Check Bank 2 TPS Signal
4. Inspect the bank 2 inductor wiring and connectors.
5. Adapt both throttle assemblies using a scanner
6. If the malfunction is confirmed, replace the throttle assembly of bank 2

Related codes

Error P0639 by Vehicle Brand