Need Help: Whistling in Engine

[MAD King]

Hello,

I have a problem and don't know what it can be.
The engine on my 1998 Lumina car is whistling when it is in idle state. As soon I get on the gas pedal the whisteling is gone. It is not the V-belt. It sound like it is coming from the engone block.

Does anyone know what this can be?

Thank you

[manicmechanix]

It could be a vaccuum hose or the PCV hose partially collapsed. I would check over the vaccuum hoses and the PCV.

[MAD King]

Do you know where the PCV is located?

[manicmechanix]

Which engine does it have the 3100 or 3800. The 3100 PCV should be in the front valve cover towards the throttle body and the 3.8 is underneath the MAP sensor towards the drive belt end of the manifold. If your noise is a squeaking sound it could also be the belt tensioner or idler.

[MAD King]

The sound is coming right from the front of the engine. If it would be the belt tensioner the sound would come from the left side, right?

btw it is a 3100.

The sound is like a tea kettle, but only if it is in idle. As soon I give a little bit speed on it the sound is gone.

[manicmechanix]

OK the driver's side is left side and passenger side is right side. The front of the engine is really on the passenger side (right side) where the belt is even though the throttle body is on the driver's side (left). So yeah the tensioner noise should come from the belt side. Since it goes away when you accerlerate it sounds like it is vaccuum related and that the noise is coming for the driver's side. That is where most of the vacuum lines and PCV are.

This might be a little hard to make out but these are your vacuum lines:
http://www.compnine.com/index.php?u=...03&grouptype=B

[MAD King]

Thank you that is exact what I need.

[jeffcoslacker]

Spray all around all the intake gaskets and vacuum lines/ports with some starting fluid, the sound will change or go away and the idle may react when it gets sucked into the leak, then you'll know where to look.

Notice any change in idle stability since it started? Another hallmark of a big vacuum leak...

[MAD King]

Originally Posted by jeffcoslacker

Notice any change in idle stability since it started? Another hallmark of a big vacuum leak...

Yes, enginge is not running that smooth like before means the speed is going a little bit up and down. Not much but I can hear and feel it.

I got a carb spray here. Does this worK?

[jeffcoslacker]

Originally Posted by MAD King

Yes, enginge is not running that smooth like before means the speed is going a little bit up and down. Not much but I can hear and feel it.

I got a carb spray here. Does this worK?

Should...keep it off painted stuff. Water works too, only problem is it doesn't creep around to the bottom of things always, and can make you miss the leak.

I was using water to find a gasket leak on my multi-carb motorcycle intake, at first it didn't show me anything. When I took the carbs off the leak was at the bottom where the intake joins the motor, the water was dripping off or burning off before making it that far down...

WD-40 works good too

[MAD King]

OK. I changed all vacuum hoses, but this howl what I call it now is still there. As soon I give a little speed it is gone, but when I get away from the speed the engine is howlin again.

[jeffcoslacker]

Did you check the vacuum line to the trans shift modulator? (low in front side of tranny, may have to look under stuff on the airbox side or follow the steel line off the back (driver's side) of the intake....

[jeffcoslacker]

[MAD King]

It turnes out that it was the L piece on the PCV. It was to soft and were compressed from the vaccuum.
I changed it into a hard one and it is gone. Engine is purring like a cat now.

Thx