BMW 325tds Automatic: Power Loss Troubleshooting

BMW 325tds Automatic, year 1996, 143 horsepower, 192,000 km.
My car has a power loss at 2000 RPM.
When I avoid the 2000 RPM range, the problem doesn't occur.
When reading the error diagnosis, it indicated that there was a fault with the exhaust gas recirculation system.
The error doesn't occur when the mass airflow sensor (MAF) or the EGR valve is disconnected. I've already replaced the MAF sensor and the EGR valve, but the error persists. I don't know what to do anymore. Please help me.