ragj1976

Hello, all. First time poster.

Just installed a DC 4-1 on my 99 EX. For the test drive it seemed to be ok. No noises. But after having dinner at a local Uno's, upon driving home I noticed a hissing, or whoose type sound coming from the center console portion of the car. It doesn't seem to happen when revving, in neutral, only when under load. I checked where the CAT meets the header and it looks ok, is a re-tourqe of the bolts worth it? Perhaps it expanded upon heating up? Any thoughts at all.. Much Appreciated..

-Rg

crak600

check it out when the exhaust is cold. as the exhaust heats up, it'll expand and begin to mask leaks a bit more. checking when cold is optimal, plus you can safely get your hands on the pipes in the first minute or two. did you use new gaskets?

could be something unrelated to the exhaust though. hard to diagnose from where i'm sitting.

CivicSiRacer

Did you reinstall the 'O' ring between the header and the cat? It's like a joint that makes sure the header when underload doesn't create a leak.

NeverBX

i second that.

ragj1976

I moved the oring from the old to the new, I have a new (from dealer) manifold gasket, I just rechecked, retourqe the stuff, took it for a ride and still the leak.. I think I'll try to replace the CAT gasket ring thing. Also, it doesn't look like the header matches up to the cat very well.. its a wee off any thoughts? (i.e. I can see the oring in the opening)

-Rg

crak600

it's a wee bit off...is it leaking or not? did you feel around the exhaust with your hand to find a leak?

ragj1976

Yea, I think its leaking.. I checked with my hand while I had it up there, I couldn't feel anything.. But the sound is there.. Does anyone know the size of the collector on the DC 4-1 (for D16), i.e. it does match up to the factory cat?

-Rg