I have a 98 civic ex with a pacesetter monza exhaust system. I love the system and the sound, but unfortunately it causes my car to rattle. It is partially due to a crack in the left side of my bumper, and due to the tip resting on the bumper it makes an annoying rattling. However, there is also a sound coming from my dash. Any ideas?

 

check to see if your exhaust system is loose or you can try moving the hangers to have the tip a bit away from the bumper

 

cut hangers, lower about an inch, re-weld longer hangars. and under the dash idk, more details? ONly certain RPMs? Metal on metal? Constant? More info about the rattle would help

 

Not really looking to lower hangars, a little much for the problem. Found a smaller lip to replace bumper that should fix the problem. It rattles mostly when idling, which is also odd because I also believe that after changing my exhaust the idle speed changed. It sounds like metal on metal. It seems to idle close to 1500 RPMs initially and after giving it gas it reduces to below 1,000 RPMs *(approx 800 RPMs)

 

Exhaust isn't the rattle, checked several times, thanks for the input though! My friend drives an LS1 firebird formula and he has U-bolts shake loose all the time and his floor pan seems to rattle, but hey, it's American, lol.

 

The resonance is probably just right to make your dash hum; as far as easy access metal/metal contact, check that your knee bolster is tight, if it's coming from the driver's side'ish.

 

I'll check into it friday when tires and rims come in and make a new post. Thank you.

 

Exhaust heat shields are notorious sources for metallic rattle in Civics. You might want to check those out.

Regarding the high idle, you might try thoroughly cleaning the throttle body, as well as adjusting and lubricating the throttle cable.

 

yea i had the same pr opblem when i got 2 half imch exhaust i took off heat sheald cut were it was hitting and put it back it idles fine now

 

Thanks guys, you're always a huge help. Got my new rims and tires in the shop for install early in the AM. If anyone could, please check out my other post about a clutch/flywheel combo, I've already ordered it and would like some opinions before I decide to keep it.