From the ribbed vee belt tensioner, rotating noises can be heard.

The ribbed vee belt tensioner torsion spring can make these rotating noises because of the first and/or the last spring winding and the spring spacer on the base plate identical rising conditions between them. When at idle speed these noises can be heard.
Models affected:
1Z/AFN engine

Parts replacement. Part number unchanged. Optimized ribbed vee belt tensioners are on the mounting bolt of the tensioning roller identified with a white mark
Gurgling noises inside the vehicle.

Models affected:
4 cyl. engines

The cooling system needs to be bled as follows:
With coolant fill up the reservoir to the brink.
From the heat exchanger pull off the LH hose until the air escapes from the ventilation hole. The reservoir has to be completely full. When the air escapes, push the coolant hose back on then tighten it.
Once you get a small gap at the top between the pipe of the heat exchanger and the hose pull off the RH hose from the heat exchanger. Do not take away the coolant hose altogether The reservoir must always be completely full. When the air finally escapes, push the coolant hose back on and tighten it. The reservoir must be filled to maximum. To create a pressure of approx. 0.5 bar in the cooling system use tester VW 1274. When in idle speed run the engine until the coolant thermostat opens. Whilst holding the engine speed at approx. 2,000 rpm, briefly press down the accelerator with strong force for a few times, this will help the air to escape from all the corners of the engine. Remove the tester and correct the coolant level when no more air enters the reservoir through the ventilation hose.
Please Note:
Hot vapors can escape so make sure to unscrew the tester carefully.

Vehicle makes a dull sound at approx. 3,500 rpm


The exhaust system shudders and are felt in the passenger position. Models affected:
Engine code AAD, AAE

Parts replacement.
Clip - Part No. 4A0 253 139 A
Flat round bolt - Part No. N 040 262 2
Hex. nut - Part No. N 011 008 18