ScottG wrote:
A similar thing happens sometimes in Dodge trucks.
It happens when a torque converter is not unlocking. When that happens and the computer senses the eng is dropping below specified RPM's, it adds fuel to the eng to keep the revs up. Since the eng is still mechanically coupled to the trans it tries to accelerate.
Not a diesel guy but this makes more sense than anything else. Computer would not through a code because it does not recognize the problem, but is just trying to keep the RPM above a certain minimum. Next time it happens, just put it in neutral. The RPM will probably be normal. It the engine does not continue to rev, then you know for sure that is the problem. If the engine does rev, then you have a different problem.
Hopefully it is not an oil leak in the turbo, or if it starts leaking badly, you will not be able to shut it off
