Turbo Leak?

**msharifi** · 11-22-2008 03:00 PM

Hi Everyone,

I have a issue when I turn the car on in the morning there is a loud noise coming from the turbo/CAT area. Would a turbo leak or CAT leak cause that? its fine after 2-3 mins when the car gets warm up.

**SeKKeY** · 11-22-2008 03:05 PM

you sure its not the secondary air pump..

**msharifi** · 11-22-2008 03:30 PM

where is the secondary air pump?

Also does the K04 turbo fit over OEM K03 turbo for replacement?

**old guy** · 11-22-2008 03:43 PM

Originally Posted by msharifi

where is the secondary air pump?

Also does the K04 turbo fit over OEM K03 turbo for replacement?

The secondary air pump (SAI) is located at the lower front of the motor. Its function is to pump extra air into the exhaust (through the combi valve located on the back of the head) during a cold start. It usually engages for about 90 seconds. Its function is to help protect the catalytic converter during a cold start. Your noise may be coming from a leak around the combi valve. It is the silver round device in the pic with the blue hose attached.

And yes you can direct replace the K03 with a K04. You will need different software and injectors.

**Turbo1A4** · 11-22-2008 03:47 PM

i would guess it was the secondary air because mine makes that noise too when i start it and i have an engine code for the secondary air

**msharifi** · 11-22-2008 04:27 PM

What is the fix on this? I do have a bad MPG even after I changed my first O2 sensor. It did improve a little bit but not whole lot. I'm half tank of gas and its been 120miles to half tank.

See the pic below the problem I have

**onceover** · 11-22-2008 04:59 PM

put a hose clamp on that?

you might have an issue with some vaccum valves if theres so much pressure in there to pop it back out.

when you open youre oil filler cap while the engine is running, is there excess pressure?

**msharifi** · 11-22-2008 08:22 PM

There is already a clamp but the metal part comes out not the rubber that is already clamped.

I'm trying to figure out why I get that loud noise and very low boost I get about max 10 PSI and goes back to like 7psi.

**old guy** · 11-22-2008 08:31 PM

Originally Posted by msharifi

There is already a clamp but the metal part comes out not the rubber that is already clamped.

I'm trying to figure out why I get that loud noise and very low boost I get about max 10 PSI and goes back to like 7psi.

The metal nipple is pressed into the valve cover and is not supposed to come out. You might want to pull the hose off and then try tapping it back into the valve cover. What you are describing now sounds like a serious boost leak. Probably a split hose somewhere. first thing I would recommend is a boost leak test.

**msharifi** · 11-22-2008 08:52 PM

How do you do the boost leak test? The DV Vaccume lines are good

**onceover** · 11-22-2008 10:36 PM

http://www.a4mods.com/index.php?page...boostleak.html

**msharifi** · 11-23-2008 10:04 AM

Other then that because I dont have a air comprasser.

**msharifi** · 11-23-2008 10:08 AM

Originally Posted by old guy

The secondary air pump (SAI) is located at the lower front of the motor. Its function is to pump extra air into the exhaust (through the combi valve located on the back of the head) during a cold start. It usually engages for about 90 seconds. Its function is to help protect the catalytic converter during a cold start. Your noise may be coming from a leak around the combi valve. It is the silver round device in the pic with the blue hose attached.

And yes you can direct replace the K03 with a K04. You will need different software and injectors.

When its making the loud noise at cold start it means its not pumping? is it only used at cold start? does it effect your MPG as I heard from others?