Please help me diagnose this sound
#1
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Please help me diagnose this sound
Guys I'm getting a strange sound from my car that I'm trying to diagnose. Any input would be greatly appreciated. Here is the scenario when I here it:
1) Very low rpms mostly at 900-1000 rpm in or 4th or 5th gear
2) extremely light throttle application at this low RPM
3) It sounds like a metallic rattling or squeaking, sometimes even can hear like its rotational if that make sense. Almost like a bad bearing in something spinning although cannot hear it in park with the hood open listening to all the pulleys and idlers. Also still present whether or not a/c, or fan is on or off
4) Can only hear it while the car is moving in drive
5) Sounds like it is coming from right under the center counsel
6) While it is doing it I threw the car in neutral and it disappeared.
I'm not 100% but thinking torque converter/ flywheel, transmission related? The whole neutral thing really has me leaning this way. Anybody heard a TC go bad on our cars? I thought when they did it was very loud. Also you cannot hear it with higher rpms or acceleration.
1) Very low rpms mostly at 900-1000 rpm in or 4th or 5th gear
2) extremely light throttle application at this low RPM
3) It sounds like a metallic rattling or squeaking, sometimes even can hear like its rotational if that make sense. Almost like a bad bearing in something spinning although cannot hear it in park with the hood open listening to all the pulleys and idlers. Also still present whether or not a/c, or fan is on or off
4) Can only hear it while the car is moving in drive
5) Sounds like it is coming from right under the center counsel
6) While it is doing it I threw the car in neutral and it disappeared.
I'm not 100% but thinking torque converter/ flywheel, transmission related? The whole neutral thing really has me leaning this way. Anybody heard a TC go bad on our cars? I thought when they did it was very loud. Also you cannot hear it with higher rpms or acceleration.
Last edited by bstudey01; 06-06-2014 at 09:37 PM.
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07 E63 + 07 CLK63CAB
The noise going away in neutral is a good sign it is a heat shield. Sons' Caddy did a similar noise while driving and on take off, it was the heat shield above the cat, never made a noise in neutral. When your drive train is under strain as in drive the vibrations are different than in neutral. Worth a look anyways, use a friend one in the driver seat and one listening near the underside of the car, e brake on for safety, go from neutral to drive, touch the gas pedal and release with brake on. Good Luck