So I hear a slight rattle coming from my car for the first 20-30 mins of it running. Seems to be coming from either intake manifold or underneath it, where headers meet cat. It also seems like there is an air pressure issue associated with this. I have to give it little more gas to accelerate, and when I do this the exhaust sounds really bad. It makes my car vibrate slightly more than it used to. After 20 mins of driving and car is warmed to normal, the sound becomes less noticeable, but it is still there, barely able to hear it though. What could be my problem?

 

"Where the header meets the cat" "seems like an air pressure issue" "give it a little more gas" Check for a clogged cat. (assuming it's still there)

-Amp

 

Ditto the above^^^ also check gaskets #10 and #19... EXHAUST PIPE for 1995 Acura INTEGRA HATCHBACK
assuming it is a stock system.

Also check #s 5,6 and 27, [covers and heat shield] 94