Knocking Noise From The Engine Bay, But It's Not The Engine

[Danny_TTE_compressor]

After doing about 20 miles on the motorway I pulled up at a roundabout, when I set off I could hear a 'once per rev knock'.... I put the clutch in and when I revved the car there was no noise. you can only hear it upto 50 ish before the once per rev is so fast its just a constant noise you dont really notice. It sounds very similar to a bottom end knock (but isnt). My first thoughts are gearbox or drive shaft (although iv never heard a failing driveshaft)

As usual, any opinions welcome.

[oldcodger]

Hey,

A really bad clutch thrust bearing ? or even the dual mass flywheel if they are fitted on your model ?

[Danny_TTE_compressor]

I thought you would get a rumbling from the clutch bearing first....