Rattle Rattle And Rev Problem

[BeemerMan]

does anyone know what this rattling sound is coming from underneath my car? i've noticed that its gotten alot louder as if there was pebbles inside my exhaust pipe rattling like crazy.

Also, when i drive it seem that my rpm maxes out at 4 1/2 and it seems like my engine is straining..... any ideas what this might be? used

[RedlinedRU]

yo man, my moms e46 had the same problem. turns out it was her catalytic converter. something inside was loose or worn out or something...not exactly sure, but it was the catalytic converter.

ps don't go to the dealership to have fixed. her fix costed 1700 but luckily it was under warranty. good luck. N

[dutchbmw]

A heat shield can be rattling to the exhaust pipe.

[Kevin325i]

Crawl up underneath it and check for a loose heat sheild. If you don't see that then hit the cats with a hammer and see listen if it rattles.

[jrhaile]

someone could have put marbles in your engine.. I've seen it before :P

[bigred318]

i had a bunch of rocks etc in my exhuat on my other bimmer, dont know how they do in there... someone must have put them there.. i agree just get under the car and listen

David

[YoungExec728]

make sure everything under your car is tightened down.

[BeemerMan]

roger that! i will check underneath my car asap. thanks guys!

[Frank]

I think its deffintly the heat shield i had the same problem and i totaly got rid of mine and viola!!

[bitcore]

ok so:
-heat shield
-catalyc converter
-rocks in muffler from kids or assholes or whoever.



ugh. thats pritty much the whole damn exhaust system :P (I've got the rattle too, Only at idle when it's in gear, occasionally at idle out of gear, so it's a resonnant rattle for me)