mpwolf

If I start my car after it has been sitting all night, 5-10 seconds after the engine starts, there is a higher pitched groan or moan from somewhere near the front of the car that lasts for about a second or two. It is audible inside the car. It does it one or two more times at 5-10 second intervals and then all is good. Anyone have any idea what this could be?

S4Tune

mine idles like it has a gopher stuffed in the throttle body...but no groan

Mike@VAST

something.

S4_Cinci (I S'edTFA)

startup (I assume that's what it is). Lasts for like 1/2 second and then goes away and no other noises.

Are you sure it isn't ribbed belt noise (accessory drive)? I've heard some belts "groan" before.

mpwolf

Might be belts, but it doesn't sound like it. Maybe I'll try to get a sound recording and post it.

Teh Goldie

Piggie, mind to elaborate further, as to why a TIP might "roar" on a start-up ??

Mike@VAST

when you first start a cold car to reduce emissions due to the extra fuel injected

Teh Goldie

Thanx.

VonK :: Retired

Don't 6 speeds also have secondary air injection?

gk1

Doesn't do it when it's warm out, and doesn't appear to come from the turbos, as I've checked with the hood up.