Help: Tweeting Sound
Thread Starter
Safety Car
Joined: Aug 2005
Posts: 4,279
Likes: 82
From: North Strand, NMB, SC; Retired x 2 (US Army: 70-90 AD) (US Army: 91-16 DAC); yea, I'm old.
Help: Tweeting Sound
The last three or four times I have taken my ’05 MN6 coupe out for a drive, I hear a “tweeting” sound coming from the engine compartment that increases as I press the accelerator and decreases when I let up.
As the engine warms up and the oil temp rises, the sound diminishes and finally goes away when the oil temp gets to 160 degrees.
The remaining oil life is at 56% according to the DIC and the oil level is right where it should be and relatively clean.
My only performance mods are a ported throttle body, ported intake, Vararam SC CAI and 4.10s. I don't track the car and shift at ~3k to 3.5k. The car performs flawlessly otherwise.
I tried to do a video but there was too much wind noise; I will try again in the garage but I don't think it will be the same without a load on the power/drivetrain.
The car has just over 48k miles on it; mostly highway.
Any thoughts as to what could be the cause?
Thanks, John
As the engine warms up and the oil temp rises, the sound diminishes and finally goes away when the oil temp gets to 160 degrees.
The remaining oil life is at 56% according to the DIC and the oil level is right where it should be and relatively clean.
My only performance mods are a ported throttle body, ported intake, Vararam SC CAI and 4.10s. I don't track the car and shift at ~3k to 3.5k. The car performs flawlessly otherwise.
I tried to do a video but there was too much wind noise; I will try again in the garage but I don't think it will be the same without a load on the power/drivetrain.
The car has just over 48k miles on it; mostly highway.
Any thoughts as to what could be the cause?
Thanks, John
Le Mans Master
Joined: Jan 2005
Posts: 5,611
Likes: 5
From: Thousand Oaks California
1st, I do not know.
But, I have had a similar intermittent noise since new. In my case, as odd as it sounds, I think the sound is coolant circulating through the heater core. If so, it may be due to a restricter placed at the heater core to control the flow rate of coolant through the heater core.
Older LSx engines have had some noise from the serpentine belt tensioner.
But, I have had a similar intermittent noise since new. In my case, as odd as it sounds, I think the sound is coolant circulating through the heater core. If so, it may be due to a restricter placed at the heater core to control the flow rate of coolant through the heater core.
Older LSx engines have had some noise from the serpentine belt tensioner.
Last edited by calemasters; Jan 14, 2008 at 11:42 PM.
Pro
Joined: Oct 2007
Posts: 538
Likes: 1
From: Niles Michigan
My guess would be a serpentine belt @ 48,000 miles. It's cheap and easy to do your self. Probably ready for one with close to 50,000 miles. Get a gatorback belt. There are angle cuts in the belt to eliminate the noise. I have had a few cars with belt noise, and noticed after the vehicle is warmed up it goes away. I installed a cheap belt and 5,000 miles later it was making noise again, so I tried one of those gatorbacks and it took care of the problem
