Hi Orel, I think someone’s been misleading you as to what the egr is. Blanking it won’t improve mpg, reliability possibly, or should I say, giving it less of an influence to affect the reliability.
I’d say your taking it to clowns for diagnosis,most mechanics, are fitters at best, they can’t diagnose faults for toffee. You’ve prob spent a ■■■■■■■■ already and got no where. Find someone you trust, someone that gives you confidence he knows what he’s talking about.