Strange metallic rattling sound underneath the car.

[rentiu]

I have a 1997 Nissan PU XE 4x4 5 sp/2.4 L engine. A few days ago I notice a strange metallic rattling noise coming from under the car anywhere between the driver seat and the engine. Another way to describe the sound is like a loose piece of metal that vibrates and hits another metalic part. The sound is not continuous, but it does appear during acceleration and deceleration with the car in-gear or in neutral . I suspect it may have something to do with the exhaust pipe...? I looked under the car and try to shake the exhaust pipe assembly, but it seems to be solidly attached with no rust holes in it.

I'm not noticing any performance loss. I was wondering if this sound could come from the catalytic converter or else?

[300max]

sounds like a heat shield is loose. jack it up check the shields to see which one is loose. I guess there is some debate about the worthiness of shields in general. maybe you can remove them all.

[bbovee]

I recently had the same problem and YES it WAS the heat shields...all rusted out so they've been removed.I've been told they don't need to be replaced...just leave 'em off but I can't help but wonder if that info is accurate. My belief is that no part is frivolously added to anything...everything serves a purpose...and if it wasn't necessary in the first place why complicate things by adding it?!If anyone REALLY KNOWS the value of having and action that should be taken would you please relay the info.

[NeedCAforS13]

just don't park in long dry grass and you'll be allright. the sheilds were put on there to prevent red hot exhaust components touching things you might park on top of. I have had mine removed for almost 2 years now and have had no ill effects due to their removal:)

Sean

[bbovee]

Thanks for the reply Sean! I had guessed that was what the heat shields were for but it's nice to have it confirmed.Especially since my car has a pretty low center of gravity I don't plan on driving or parking it on uneven terrain...hence...no concern.Matter of fact I went fishing at Honeymoon Island last week and got stuck in just a few inches of sand on the drivepath...had to resort to my MA talents for driving in snow to escape.

Thanks again, 'B'

[nailed]

do the 240sxs have this too? because i get this same rattling noise when i get the car up in the higher RPMs. i thought maybe it was my front bar....

[Und3rprshUr]

do the 240sxs have this too? because i get this same rattling noise when i get the car up in the higher RPMs. i thought maybe it was my front bar....

yea that or bad exhaust hangers.

[bbovee]

...just have to razz ya a bit but, at the same time, enlighten you.You mustn't have noticed that in the left column (user i.d.) as well as in the previous threads, you will usually find what vehicle is being discussed!:thinker

[NeedCAforS13]

its a common problem on alot of cars I would say. My 240 does it, as do almost all of my friends' 240's and even my friend's integra did it until we removed the shields:)

Sean

[SilviaS14KA24DE]

hmm i removed most of the shields, but it still rattles, sounds like it's coming from the cat....

[SilviaS14KA24DE]

or maybe the heat shield above the resonator right after the cat? bu the resonator looks like it's welded on. Any ideas how to take it off?