i have noticed the past couple of weeks that when i start my 2.7t i've been hearing a siren type of sound. it's kinda like a jet engine that goes up in pitch. but when i turn my climate control off the noise ceases. what is this? i hear it more towards the front of the engine.

 

If you are using the AC, it could be the electric cooling fan up front.

 

What has the weather been like lately?

 

siren sound is a symptom of your turbos going...any oil leaking from your exhaust?

 

i would think turbos, but it quits when i turn climate control off. it does it when heat or ac is on. i'm baffled!

 

any thoughts?

 

I have heard of the heater fan making noise, but no ideas from me.

Thanks

Jason

 

Like I said, cooling fan(s) Even in the cold if you use the defrost the AC cycles which causes the electric fan up front to turn on. Put someone in front of the car and cycle the climate control, with the hood open. That is unless you are a recluse and have no friends. Then you will have to live with it.

 

its the secondary air pump used on our cars to warm up the exhaust when you start it up in the morning, hence the noise isnt really made the rest of the day. During the rainy season my car would make that whine then it would stop. in the warmer weather it doesnt make that noise. The theory of turbo going bad the siren noise would be consistent not just momentarily like a 20-30 sec warm up. The secondary air pump makes a whine / drilling / turbo spool noise. imnot sure how much it costs to replace but i remember it not being "TOO" bad and it wont really do anything in terms of real damage. from my understanding that is.

 

I had the same problem with my 2.7t, I took it to the dealer, they replaced the 'secondary air pump' under warranty. The car is also very loud when the AC is on. I just press the ECON if it's cold outside. If it's hot, I just deal with it.