U0691

Symptoms

• Check Engine light comes on
• Reduced engine power
• Increased fuel consumption
• Problems with the exhaust gas recirculation (EGR) system
• Possible errors in pressure in the exhaust system

Causes

• Open or short circuit in the sensor circuit
• Poor contact in the sensor connector
• Malfunction of the exhaust gas pressure sensor
• Problems with power or grounding of the sensor
• Engine control unit (ECU) malfunction

How to Fix

1. Check the integrity of the wiring to the sensor
2. Inspect and clean the contacts in the sensor connector
3. Check the power supply and grounding of the sensor
4. Replace exhaust gas pressure sensor if necessary
5. Check and update the control unit software if necessary

Related codes

Error U0691 by Vehicle Brand