Car is a 2001 Audi A4 quattro 1.8T

I purchased this car with approximately 50,000 miles on it. When bought the car it had NO[/b] strange sounds and ran perfect. Recently, I noticed there was a loud “clicking” sound coming from the rear of the engine during startup (hot and cold). I dropped the car off at my local Audi dealership with suspicousion that it was the cam chain tensioner causing the noise. The service technicians agreed that it was the cam chain tensioner and quoted me a price to replace it. I decided to take the car to AutoPro Inc. due to a cheaper price and convience to where I live. They stated it was the timing belt tensioner caused the noise therefore they replaced the timing belt tensioner (both parts/roller and assembly) and replaced the timing belt. The sound did not go away! However, they did notice that the Vacuum Connector assembly hose had a hole from heat and was making the check engine light go on. They replaced it and the light went off. AutoPro then diagnosed the car and discovered it was the Combination Valve for the emission system. They replaced it and the sound still remained. They even got another Combination Valve thinking that it was a defective part. After a few days with my car in the shop and AutoPro discussing the situation with Audi and other various technical services they concluded that the sound was “normal”. They even called the Audi service department in front of me and were told that this sound is normal and can last up to 45 seconds during startup. I do not agree[/b]. How can this noise be normal when it did not do it when I bought the car? It is definitely coming from the Combination Valve but something is causing it to make such a loud sound. All this happened around 68,000 miles and just recently (76,000 miles) I took the car back to the Audi dealership for bodywork and to diagnose the sound again. They stated that is was still the cam chain tensioner. So let me get this right, the noise is coming from the Combination Valve which has nothing to do with the cam chain yet they say the cam chain tensioner is making the noise. WTF! Can somebody help me? What would cause the Combination Valve (which is brand new) to cause a loud ticking noise during startup??

 

The combi/check valve is supposed to tick. That means its working. It shouldnt be very loud though. It could very well be the cam chain tensioner. Its not uncommon. Does the sound go faster when the rpms go higher?

 

Yes, the sound is Loud! Only for a very short time though, for instance, when you turn the key to start the car the noise is made and by the time you let go of the key the sound is just about finished. And No, when I give it gas the sound does not increase with RPM. I'm just really confused because I know the valve is supposed to make a noise but what is causing it to be so LOUD. I am 100% positive that the sound is coming from the valve.

 

Figured it out.....it was the cam chain adjuster. Cost a little over $1K to replace. Only reason I took it in was because the cam shaft seals started to leak and the car started leaving it's mark everywhere I parked!