Rattle in park or neutral

Hi and thanks for using 2CarPros. Com. First, it is difficult not being there to hear the noise. You mentioned a rod knock and then a rattle, which are two very different things. Is it possible for you to upload a video of the vehicle making the noise so I can hear it?

I have to be honest, I like the way you think. If it is a rattle, to me it sounds like an internally loose catalytic converter or heat shield, which are pron to make noise at an idle or lower RPM's. If you are certain that is not the problem, until I hear the noise I would suggest removing the accessory belt under the hood and starting the vehicle for a few seconds to see if the noise goes away. It could be a belt driven accessory or a tension-er bearing. To be honest, I feel you would hear a rod knock and just about any RPM and not just at idle. I have a feeling because if its location, it is one of the belt driven accessories or still related to the exhaust. Please upload a video so I can hear it.

Let me know,

Joe

Okay. Of course my car will not do it when I want it to. But here is what I know:
When starting the car, it will sometimes sound like something metal "pops". Sometimes only once, sometimes multiple times. Car always starts. After warm up, you will hear (only in park or neutral) a sound I can best describe as a rattle. Kind of resembles a rod knock and is low, but may not be. I will continue to try to get a video. Could it be the flex-plate? There is also a surging feeling at light throttle, but no check engine light illuminated.

Also, I replaced the motor mounts but could not get to the one located down in the back. But attached is the video.

That sounds like a cracked flex plate. To eliminate anything on the front end you could remove the accessory drive belt on a cold engine and start it. If the noise is still there it is not the accessories. You might be able to slip a camera up into the bell housing and look at it directly. Or use a mechanics stethoscope to listen to the parts of the engine and track it down.

Still wondering about that back motor-mount by the firewall. But I am not certain I can do that one myself. I know you have to remove the CV axle to do it on this car.

I would remove the serpentine belt and start the engine. If the noise is still there it will be the timing belt and tensioner problem. Thanks for the video really helps.

You will need to remove the front balancer. To get started here is a guide that will show you how and the diagrams on how to change the timing belt and tension-er:

https://www.2carpros.com/articles/how-a-harmonic-balancer-works

Check out the diagrams (below). Please let us know what happens.

Cheers, Ken

I have done the timing belt prior to the first post on this issue. The car was making noise before the timing belt. I installed a new water pump, timing tension-er, and timing idler. Did not do oil pump.

Can you remove the serpentine belt to see if the noise stops?

The next time I have a chance will be Friday. Will update then!

Let us know. :)

Okay, the long awaited update. I have replaced the trouble motor mount. Still had noise. Took the car to a transmission shop and turns out the flex-plate is bad. So that is going to be a fun repair!

They are not that bad if you can find a shop who has done a few. You canpull the mounts on the engine and trans and gently split them just far enough to get the bad one out and slip a new one in. The biggest hurdle is getting past the front pilot on the converter.
There is a lot of stuff to unbolt to get to that point though so those two can move apart. If I recall it is an hour or so less than pulling the trans-axle out.

I am willing to pay the extra so they can do the rear main oil seal and the torque converter seal as well.

Okay. Then they will need to pull one or the other out to get room for that as the converter has to come out.