My Dodge Dakota does not exceed 2000 rpm !!!

Hello friends, I have a question to ask them. I have a Dodge Dakota 2.5 TD Model 2001. The truck has a failure and I do not find the solution. The problem occurs when it reaches 2000 rpm stagnates there and does not exceed them. I already pass through several workshops and there is no solution. I was reading a lot about sensors but I'm already lost and I don't know if the fault can come there. I appreciate any type of contribution thank you very much!

Did you try to measure fuel pressure?

Yes. I have already controlled everything and everything is fine. In the only way that is solved but it fails again is connecting it to the computer and erasing the fault but lasts one or two days and returns to the same.

Hello MACIA a question !!! It gives you error codes the ECU ???

What is the problem that the computer tells you?
When do you delete the code does the truck work in good condition?
Is there any sound that makes the engine or transmission?