P2413 EGR Performance Fault on 2010 Mitsubishi L200/Triton - Diagnosis and Fixes

I'm experiencing a persistent P2413 (EGR performance) fault on my 2010 Mitsubishi L200/Triton. Despite spending significant time and money, I've tried numerous solutions without success. Steps taken so far include: - Complete removal and cleaning of the intake manifold; - Replacement of the EGR valve; - Replacement of the MAP sensor; - Replacement of the MAF sensor; - Replacement of the vacuum hose (manifold to MAP); - Replacement of the manifold temperature sensor; - Replacement of the EGR cooler; - Replaced the EGR valve a second time. The issue is intermittent: when the engine is cold or after resetting the battery terminals, the EGR valve operates normally during idle. However, as soon as I accelerate beyond 3000 RPM, the valve begins to malfunction—either shutting completely at 0% open (or 0% and 99.2%) or failing to respond properly. An additional symptom occurs when the EGR is functioning correctly at idle: there are instances of coolant loss, with visible drips under the engine. Interestingly, when fuel levels are low, the P2413 error code does not appear at all. My questions are: - What could be causing the new EGR valve to shut during acceleration? Is it a fault in the ECU or an electrical issue? If so, why does this behavior only occur under load? - Could there still be a collapsed, blocked, or split vacuum hose—other than the one already replaced—that is affecting performance? Which specific hose should I inspect? Any insights or troubleshooting tips would be greatly appreciated. Thanks for your help!