sounds like my 2001 a4 1.8t is a deisel heavy ticking out of the engine
have you filled it with the correct oil ?? the 20VT has to have a specific oil, other wise the auto adjusting valve lifters (Tappets) get sticky and this is the ticking you are hearing !! I make this mistake the 1st time i serviced my 20VT. It's worth popping down to your local VW/Audi dealer and spending a little more on the correct oil, or you will cause more and more problems the longer you run the incorrect oil.
No Check Engine light correct? I always ask this because from time to time, I'll find a vehicle with a bad spark plug wire that is arcing to the valvecover and produces a noise very similar to a valvetrain noise. That being said, I agree with the above statement on going with the correct oil. You likely have two or three recommendations based upon climate; that's how most manufacturers are doing things nowadays. Beyond the oil type and weight, it's a toss-up without starting to take things apart or at the least, stethoscope it. It's possible that your noise is in the accessory drive and is not internal at all. Turn your A/C off and see if the noise goes away. If it does, it's your A/C compressor. If it doesn't, to isolate the accessory drive system, remove the belt carefully and set it aside, taking note of which direction it was installed and reinstalling it the same way (only to reduce the chance of it squealing upon reinstallation.) Start the engine and run it. If the noise is gone, shut it down and spin each pulley by hand listening for metallic noises and feeling for wobble play or excessive force required to spin it, though obviously the force will be different for each pulley depending on what it's driving. DO NOT RUN THE ENGINE FOR LONG or at excessive rpms because you're going to be running on your battery alone and it may overheat, assuming the water pump is accessory-driven and not cam-driven).
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