"I've heard that the car will run fine without EGR, and that performance may actually improve. Is this true?"
Yes, you can disconnect them and plug the vacuum line, but my thoughts are to leave them alone - disconnecting them DOES NOT appreciably improve performance. Removal can cause "ping" when the engine is hot and affect gas mileage. They only work at high port vacuum and high temperature anyway. Their purpose is to cool (strange - hot exhaust cools?) the combustion gases, lower temperature, reduce detonation and reduce HC (NOX?) emissions. Some performance theorists believe that by disconnecting the EGR the air/fuel mixture is always higher in oxygen, giving faster re-acceleration after backing off on the throttle. I've tried it with and without. I choose to leave mine connected.
From: Randy T. Agee
The ECM DOES NOT control the 2.5's EGR valve, or know they are there - except for the O2 content in the exhaust.
From: Randy T. Agee
The EGR valve on the V6 is controlled by the EGR solenoid, which is controlled by the ECM.
EGR valve | |
EGR line(s) | |
EGR solenoid (V6 only) | |
EGR tube (V6 only) |