My car has all of the sudden started making a weird noise. As soon as I let up on the cultch and enter 1st gear and take off slowly a loud boing, bwaaaaa noise comes from the rear of my car. I have slp loudmouth system, but it doesn’t sound like an exhaust note. I also do not think it is a low torque sound either. I have not made any changes to the drivetrain either. The noise usually only happens when the car is cold and still warming up. Occasionally the noise will come back while I am entering 1st gear slowly, and giving it very little gas. I am thinking it could be the differential or something with the drivetrain, or maybe piston slap, the car is new (2002). The noise started after when I accelerated at about 75% throttle and shifted into 2nd where the road got bumpy and my foot was pressing on the gas back and forth, the car was around 4,000 rpm. Besides that I normally drive the car easily and try not to abuse it. The car is not driven that often too. I would also like the note that I have not lost any performance while hearing this noise. My acceleration is still the same and the car runs great, and i do not have traction control so that is not making the noise. Has anyone else had this problem, is this a normal noise? Please help, thanks for your time and feedback!

 

Hummm...

1. Check the obvious, get under the car and wiggle the exhaust. Likely it is the pipe going over the axle hitting the heat shield, my car did that for a while until I got things lined up with my Corsa.
2. Check the fluid level on the rear end just in case
3. Are you feeling a klunk when you take off in 1st? Or are you just hearing this noise?
4. Piston slap is only noticeable for a few min until the car warms up, after that you'll not hear it again.
5. Check your rear trans mount under the cross member to make sure it's not failed. You'll need a jack and stands for this one.

 

Thanks for the info, ill try everything you mentioned. I am just hearing a noise when the car starts moving. I do not feel a klunking when i take off.