Very quite "knock" sound when first moving

[Z-Knight]

I'm sorry if my posts about subtle sounds is overly paranoid, but I paid nearly $30k for a car and having any weird sounds after 1 year that I don't recall hearing before are scaring me.

I have a 2011 Rogue, SL, AWD and I currently live in Houston so the weather is not really an issue. I have this very subtle, hard-to-hear knock sound when I first get rolling. Initially I thought it was related to me backing up since I started to hear it when I would back up from my driveway and then when I would start to drive forward, but I can also hear this sound if I simply start to move forward immediately (i.e. without having to back up first).

The sound is quite and sound muffled and I've tried opening the windows to figure out where it was coming from but I can't. The following is how I can reproduce it: start the car, put it in drive and let foot of brake. As it starts to move (without me adding gas) I will hear this quite "knock" sound just once - probably after 15-20 feet of moving. I CAN NOT reproduce it if I simply stop at a stoplight and then start again - it only seems to happen from a powered-off stop.

The thing that sucks is all of these new sounds are happening after having a 15 mile service/check and so I'm getting worried I had incompetent service - they did say they adjusted my alignment so I wonder if that is somehow related to that. It was surprising because I never hit any potholes or went off-road so I don't see why my alignment would be off - but I'm a sucker so I paid for it.

Any thoughts would be appreciated on this topic. Thanks.

[ImStricken06]

its your brakes, and or ABS system.

when you stop the car, you apply the brakes. the brake pads mate with your rotors, and when you pull off, it can at times cause a deep click noise. and our ABS system makes noise when first starting off on a roll.

[Z-Knight]

Thank you for the response. Shouldn't I also hear this sound after starting from a stop light? I only hear it when I start moving from a powered off stop - i.e. I can turn the car on, start moving and I hear it, then I turn off the car and repeat the process and it happens again. If I start the car, drive a little and brake and then release and continue then I don't hear it.

Also, I don't hear it immediately after removing my foot off the brake...I hear it about 15-20 feet later when I'm gaining some of my speed (without applying any acceleration).

Do you think this could still be related to the ABS, as you surmised initially? Thank you.

[ImStricken06]

then thats the ABS system doing its check.
just in case, try the dealer just to make sure. you dont wanna joke around with the brakes- thats your life line.

[Qashqai]

Check the page 5-28 of your owner's manual. It says:

Self-test feature
The ABS includes electronic sensors, electric pumps, hydraulic solenoids and a computer. The computer has a built-in diagnostic feature that tests the system each time you start the engine and move the vehicle at a low speed in forward or reverse. When the self-test occurs, you may hear a “clunk” noise and/or feel a pulsation in the brake pedal. This is normal and does not indicate a malfunction. If the computer senses a malfunction, it switches the ABS off and illuminates the ABS warning light on the instrument panel. The brake system then operates normally, but without anti-lock assistance.

[ImStricken06]

Check the page 5-28 of your owner's manual. It says:

Self-test feature
The ABS includes electronic sensors, electric pumps, hydraulic solenoids and a computer. The computer has a built-in diagnostic feature that tests the system each time you start the engine and move the vehicle at a low speed in forward or reverse. When the self-test occurs, you may hear a “clunk” noise and/or feel a pulsation in the brake pedal. This is normal and does not indicate a malfunction. If the computer senses a malfunction, it switches the ABS off and illuminates the ABS warning light on the instrument panel. The brake system then operates normally, but without anti-lock assistance.

great post. i just wanna add that the colder temps, make fluids much thicker - so extra noises should be expected. its really hard to get the cold fluid to move, so sometimes the thumps are simply partially lubed things moving around.

[Z-Knight]

Thank you both VERY MUCH!!! I looked in the manual to see if there was a "troubleshooting" section and never even thought to check the brake section. Thanks again, I feel better but, as you say, I will make sure when I go in to the dealer.

[ImStricken06]

Thank you both VERY MUCH!!! I looked in the manual to see if there was a "troubleshooting" section and never even thought to check the brake section. Thanks again, I feel better but, as you say, I will make sure when I go in to the dealer.

not a problem. just swing by and ask to talk to a service manager. im sure its normal, but you do want to be careful. glad we could help just dont forget to update us when you go and the result.

[jcircus]

ahhh, my wife has been complaining about this exact same thing on our 2012 Rogue SL. You only hear it when first leaving the garage after a cold start.
Thanks for the info!