Is anyone else having this?

After the car has not been started for a couple of days (or more), I hear a "dunk sound' when I start the car. This is followed by a rattling sound that goes away in about 2 seconds. What is this?

 

I heare the same dunk sound you are talking about. I think it does that as soon as you turn the key to the acc position. It seems to be turning the fuel pump on.

I also hear the rattling sound and I am puzzled about this one too but It seems to come from the gear box. Mine only does it everynow and then specially when it is too cold (20 to 30 F).

 

My "dunk" sound happens as soon as I am turning to motor over... then the motor starts....then a rattle sound follows for a few seconds. I'm worried I may have a serious problem. This happens only when it has sat for a couple of days....or more. I followed proper breakin procedure and have never taken it up to redline.

I am hoping this is normal.

 

Check to see if your air conditioner/fan control is on automatic. Try starting it next time with the fan switch turned to off and see if you here the noise.

 

You are hearing the ABS unit go through a self check routine. The owners manual says this somewhere in it.

 

I am also getting the same matallic dunking sound. It is only for a couple of seconds then it goes away. I dont know if I should take it to the dealer. Are you sure that this is the ABS. Yes it does happen more often when its cold and the car has been sitting for a while.

 

hmmm.. the only dunk sound i experience is when i turn on the AC. Maybe thats what you guys are hearing If your fans are set on Auto.. just as another person mentioned... it turns on the A/C automatically on start up. Try turning off and on the AC button. See if its the sound you are experienceing. Just a thought

 

I'd have to agree. My Audi does the same thing. Occasionally clunks right when you first start up the car. This is mentioned in my Audi manual. Does the 350's manual not talk about it?

 

I agree: It's the ABS self-check.

It is in the owners manual on Page 5-21.

 

1) I religously turn of my AC (auto to off) prior to shutting the car of. Therefore, when starting, the AC unit is off.

2) There are, essentially, two noises:
a) The "dunk sound" occurs immediately when the motor fires. ("dunk vrooooooooooom")
I would not expect this to be an ABS test. Especially since it only does it after the car sits for a few days. I would expect the ABS test to occur (and therefore the dunk sound) every time the engine started.

b) The "rattling" noise occurs right after the "dunk sound" for approx 2 seconds.


Thanks in advance for your input on this.