I believe the inoperable vacuum pump will have a greater impact on your HVAC operations [if equipped with MVA] if the MVA (manifold vacuum assist) connection has not been blocked or capped. I do not think it would impact engine performance in the manner in which you are describing.

If you can extract the "Actual Values" from the engine managemnt system it may be helpful in identifying a cause to your complaint.

The most significant values would be

• Oxygen sensor readings
• MAF Volume
• HFM Voltage
• Partial Load Adaptation
• Idle Speed Adaptation

I see the message is directed to DOC and Steve..................