06 GP L32 Engine noise

**GeeBee** · 08-11-2009

Ok i've got a bad feeling about it cause its not a lifter tick and it only has 45k on it.(only about 500 of it from me) Car drives fine and engine / trans feel good(aside from cruise control locking(unlocking it w/o reason) I dont have a scanner / tuner yet but theres no SES light.

Engine - Stock w/ Wizair - running 93 Octane @ almost sea level

Sound - Almost like an exhaust leak but more muffled....or light scratching - it doesnt really sound like metal on metal but if it is its minor. sound isnt noticeable from inside w/ windows up.
EDIT - Went out and remote started it and remote killed it while listening to the bottom end.....could hear it slow down and kind of clunk before it stopped...my guess is rod-crank bearing.

Symptoms
Its very noticeable when first starting it up, seems to go away once it gets warmed up.

It sounds to be coming more from the bottom end, either the trans or rotating assembly. Maybe power steering pump....but i doubt it sat in park and turned the wheel back and forth and it didn't change. A/C Compressor on / off didnt change sound other than engine load / rpm adjusting. There is a squeak in the alternator at start up but it doesnt feel rough.

I switched it to 10W30 Mobil 1 synthetic from 5W30 due to the warm climate. The oil is good and it has about 500 miles on it - the oil is still clean on the stick but smells a little gassy.

Guess ill be driving the Olds until i get a diagnosis.....just installed the fanceh head unit in it too....so much for the headers i was planning on getting>=(

**bbptech** · 08-12-2009

Do u hear the noise if u rev it up?

**BillBoost37** · 08-12-2009

A bearing going bad is not common on a cold start, it's more common once warmed up (oil thins) and a slight rev usually allows you to hear it.

Cold starts, I've heard of wrist pins making a little noise or something else..a coupler maybe?

Those codes would probably be a big help.

**minichopper6hp** · 08-12-2009

If the noise is only on startup i would check the harmonic balancer to make sure the rubber isnt torn, just an option, not likely on low mileage but you never know. Where in florida are you?

**GeeBee** · 08-12-2009

Melbourne, have it parked atm, going after the dealership on the warranty atm.

**Gregorius** · 08-12-2009

I Quoth:

Symptoms
Its very noticeable when first starting it up, seems to go away once it gets warmed up.

End Quothing.

My stock answer for anything that sounds like a lifter, but isn't a lifter is to tighten the exhaust manifold bolts

Especially when it warms up, the sound starts going away, or lessens.

Probably not even a bad gasket. Just loose bolts.

**Swash** · 08-12-2009

^ could very well be.

You quoth? Does that hurt?

-Swash

**carling** · 08-13-2009

I had a very similar problem with my car ( 2006 gt ). It turned out to be the inspection cover ( transmission ) rubbing the flywheel.Apparently there is a TSB for this.Try dropping the cover and see if your noise goes away.

**Gregorius** · 08-13-2009

Originally Posted by Swash

^ could very well be.

You quoth? Does that hurt?

-Swash

Depends on how much I'm getting paid.

**GeeBee** · 08-13-2009

Originally Posted by carling

I had a very similar problem with my car ( 2006 gt ). It turned out to be the inspection cover ( transmission ) rubbing the flywheel.Apparently there is a TSB for this.Try dropping the cover and see if your noise goes away.

Now that's a nice alternative to what i've been thinking....going to look into that