what is the noise?

[bex]

more questions, always like that with a new ride.

anyway, just bought 2003 eb 4x4 v8, when driving and under acceloration, there is some noise from the motor area, sounds like well....like coins in a can rattling or water pressure being applied to a pipe and the air is still in it, hard to describe.

it goes under acceloration, but it is not loud at all, can still easily hear the engine over it, it gets quiet when i let off of it or when just accelorating lightly at higher speeds.

any ideas? it almost sounds normal, but this is the most high tech car i have owned and the only car i have bought that i know hardly anything about.

 

[2Mercs]

What you are describing sounds like detonation, which is the firing of the gas/air mixture in the cylinder in 2 or more locations instead of the ignition point by the spark plug. This is a bad thing. I'm not sure if these 4.6's have a knock sensor in them or not-they are supposed to adjust the engine timing, etc. to avoid this. If it's severe it can do long-term damage to the engine. Failed intake manifold gaskets can cause this. Maybe someone who knows a bit more about the layout of the 2002-up's can chime in. Most of my experience is with the 96-98's.

 

[bex]

an update, the noise comes even at idle, it is off and on but mostly on, sounds like something is lose maybe? after 45mph when it kicks into i guess
5th gear, the noise goes completly away.

i do not feel any vibrations or anything unusual with shifting or nothing, just the noise.

i am thinking something might be lose, will look more or take it to the dealership.

 

[muzzymaniac]

Check the heat shield on you cat. They tend to loosen up over time.

 

[sjr033]

Check the heat shield on you cat. They tend to loosen up over time.

x2

 

[Charlie]

Check the heat shield on you cat. They tend to loosen up over time.

x3

Sometimes pebbles get stuck in them too

 

[ROBERT S]

Last June my 2002 Mounty AWD V8 started making a rattling noise, as describe above. It sounded as if I had a diesel engine. Idling or eccelerating it made the same sound. A local Lincoln Mercury dealership check it out and said it was my torque converter. They replaced it under my warranty and the sound is gone.

 

[bex]

that is what mine sounds like also, a diesel engine, reminds me of my psd i use to have only quieter.

i will take it in to have it checked out.

 

[muzzymaniac]

Well loose coins and diesel motors make to very different noises.

 

[bex]

maybe so, but the constant description of "rattling noises" leaves a very open ended interpretation.

narrowing it down upon further analysis plus my own experience with driving just a diesel for years, it does indeed kind of sound in a way like a diesel, driving it reminds me of driving my old psd around or the pajero diesel.

either way, had it less than a week and already something wrong with it. with all of 54k miles on it.

 

[Exrange]

mine was making the same noise....ended up being the flex plate that had a few cracks around where it bolts to the torque converter. this mysteriously happened after the dealer replaced my transmission a month later. they wouldnt own up to it because they said its a common problem

 

[charlesecarter]

To owners of Explorers with the torque converters that were replaced and it improved symptoms....What did the service tech say was causing the rattling noise in the older torque converter?

I am curious if it is just a noise or could something turn loose and ruin the trans????

Charles Carter