Hi guys

I've recently bought a leon 2.0 tdi 170 with dpf issues which I had the dpf deleted and a dpf delete and tune file done too. After this if you was in 4th 5th and 6th at 1500 rpm and pressed the accelerator the car would vibrate like mad as if the flywheel was knackered but it didn't feel like a flywheel rattle , I was told it was possibly the injectors so changed the injectors and now the car seems to have no power between 3000-3500 and then really struggles to get to 4000rpm. We changed back to the standard injectors and detuned the car leaving just a dpf delete file on the car which eradicated the vibrating issue but the car still had the same symptoms of loss of power. Is there anything else it could possibly be as it'd driving me crazy to say the least , also I changed the fuel filter and it's showing no codes on VCDS ! Any help would be much appreciated 👍