Whenever im at a stop. The car makes this rattling noise underneath . like a clunking noise. What could it be...

I have a 99 e320

 

exhaust pipe / shield touching something?

 

The noise is coming from underneath the driver side near the engine. Could it still be the heat plate? What should i do? Could it be time for an oil change or spark plug change? Thanks

 

that depends on what kind of noise.

best way is to lift the car up and simulate the noise. you might be able to pinpoint the source.

be very careful when you're just jacking up the car and crawl underneath. you might lose some limb or cause death which could get a nomination for darwin award.

 

Hi,
Clunking or like marbles rolling around. Disappears when engine is turned off?
Check exhaust heatshields first as stated by Sleepwalker but I suspect that you will find that it is ceramic monolith in the two catalysts positioned either side of the gearbox.
The V6 320 is extremely prone to this problem which is usually most noticeable when the engine is cold. You didn't state mileage but I will guess it's 80,000+ mls. Correct?
All you have to do to confirm diagnosis is to tap/bang the catalysts (Take care. They are HOT) when the vehicle is on a jift.
New half exhaust system is the only solution.
I'd be interested to know how much these are where you live.
Stuart

 

Thanks for all the help....

I looked underneath the car and whenever i pushed on the pipe underneath the rattling would go away. Is that the heatsheild or the cat.

It is right underneath the car

Please advise

 

Here is an update...


I went to my car and looked underneath while it was running. It was making that noise again. So i started to tap o the pipe right under the car and i could hear something bouncing around... It sounds like a pebble or something.. When i tap it the noise goes away. What could it be?

 

it can be the catalyst as snanceki mentioned.

from which area on the diagram?

[IMG]local://upfiles/1/DE615C6D20F2417AA49578265D823C82.jpg[/IMG]

 

what does that mean? Whats making the noise? Did something fall in their or did some kind of piece break off. The noise is coming from that big round thing in between 20 and 90 in the middle in the diagram. It sounds like there is a srew or a small pebble moving around in it.

 

that's the catylytic converter.

the catalyst inside was broken and making the sound especially if you blip the throttle.

it needs replacement.