So I have noticed something really strange that I am thinking Nissan will have a hard time diagnosing (if it is even an issue).

After I run my car for a moderate (or longer) period of time... and put it in park, I notice a PING noise. The noise can best be described as sounding like someone taking a rubber mallet and striking a metal container. It always happens only once... and I can reproduce it easily after a drive of 5+ miles at varying speeds. If I drive less than that, it typically doesn't happen.

Other things of note... it will happen whether the car is still on, or off... but the consistent thing is that it happens AFTER I shift the tranny to Park. My perception is that the sound is coming from the lower section of the engine and/or right behind the firewall.

Any thoughts on this mystery??

 

If you can, (safely of course) try and record this phenomenon.
I am interested in this "PING" sound.

Also, it seems like the problem can be easily reproduced, so your potential trip to the dealer will be a bit easier.

 

Have you taken it to the dealer?

 

probably the parking pawl engaging, basically the little piece of metal that keeps the car from moving in park. usually you can hear it engage louder on an incline

on automatic trans, always apply the E-brake before you go into park. that way the brakes take all the weight and not the parking pawl. hills especially are hard on the pawl, the whole cars weight is held by that little piece of metal if you dont use the E-brake

 

I was thinking the same thing, but was misled by the member's statement of So, OP: Can you easily reproduce the problem of driving say, 10 meters, then placing the car in park? Or does it have to be at least 5 miles?
What type of roads are you driving on? How fast is your rate of acceleration?

 

Ah, good suggestions here... I will try the e-brake before park idea to see if that solves the mystery. I've not noticed the noise if I make a quick trip and park... only on trips that are of a longer distance (thus the statement about 5+miles). The odd thing if it is the parking pawl... is that it sometimes takes 1-2 minutes after I put the car in park for that noise to appear. I always use the e-brake, however I almost always apply it after the car is in park, but before I release my foot from the pedal.

I am waiting until my next oil change to bring it up to the dealer, unless I figure it out before then. Unless it is a concerning issue, not something I want to hassle with a separate trip on.

 

Please report back and let us know when you do.

 

Alright after finding more time to tinker with this issue and listen closely for it, I *believe* it might be a head shield of some sort that is expanding and then contracting. What lead me to think about the shield was hearing the sound the other day after the car had been turned off in the garage for a good 20-30 minute span and hearing the noise while I was out there. This also makes sense as it would take it a while to get up to full temp and start to expand etc. On the trips that I took which were shorter in distance, I never heard the noise.

I'm going to ask about it on my next service visit.

 

I know exactly what noise your talking about, pretty sure it is just normal noise when your engine is cooling down. Def nothing wrong.

 

The "ping" noise is normal and the catalytic converter heat shield can be adjusted to make it ping less.

When Nissan replaced my short block I had the ping noise ( was not there prior) as they must have moved the heat shield when reassembling the motor.


Ping is normal, below is not

http://forums.maxima.org/7th-generat...-problems.html

 

If this involved the tranny, the ping would come exactly at the time you move the lever to park, not later. This almost has to be heat related, and the logical place would be a heat shield, most likely the one next to the catalytic converter.