strange knocking rattle at 1000 to 2000 revs tdi 110

[mjrplan9]

hi i just started getting this problem the other day...when im driving the car between 1000-2000 revs and plant the accelerator to the floor the engine or gearbox noise gets real loud like a major rattling rumble almost as if the exhaust has blown but the exhaust is fine..1st gear sounds good so does 2nd most of the time but 3rd 4th and 5th are awful when you floor it...but sometimes when ive idled the car the knocking noise would go tick tick with the idle speed...has anyone ever came across this issue...99 tdi 110 5 speed with 100k

any suggestions would be appreciated

[mjrplan9]

hi i just started getting this problem the other day...when im driving the car between 1000-2000 revs and plant the accelerator to the floor the engine or gearbox noise gets real loud like a major rattling rumble almost as if the exhaust has blown but the exhaust is fine..1st gear sounds good so does 2nd most of the time but 3rd 4th and 5th are awful when you floor it...but sometimes when ive idled the car the knocking noise would go tick tick with the idle speed...has anyone ever came across this issue...99 tdi 110 5 speed with 100k

any suggestions would be appreciated

has anyone got any ideas what i should do to try and source this problem?how would i know if its an engine issue or a gearbox problem?