Engine makes strange noise at mid temperature
Hello, i want to expose a recent problem with my 1.9jtdm.
I have a strange kind of friction/scratching noise comming from the engine when the car is almost reaching 90ºC. I only happens when i accelerate and it stops when i remove the foot from the throttle, and it happens whether i have a gear engaged or not.
The strange is that it happens only for 20 to 30 seconds, regardless of the RPMs or the turbo pressure. After this short period it never makes that noise again until i stop the car for a few hours (until it reaches a low engine temperature), and then start a new trip.
Until now the only three guidelines that i have is the temperature (below 90ºC), it only happens when giving some throttle (just a little is sufficient) and it only happens for a short period of time ( around 30 seconds).
Have anyone experienced something similar?
Any help is much appreciated.