so I've been fighting this noise that sounds like an exhaust leak, but I cant find one. I have replaced all header/collector gaskets numerous times. I have an 86 iroc, it has a 350 in it, oval port with headers. sounds fine when i'm idling, even revving, but when I put it in gear and give it gas under load it sounds like an exhaust leak. Its the 2 into 1 exhaust style, pic attached. Anyone else have this? is it just a characteristic of the car? Its driving me nuts. My dad said thats just how it sounds but I dont believe him. I've felt around and cant feel any exhaust coming out of anywhere, maybe i'm loosing my mind

 

I had a similar problem. turns out it was the speedo cable. It didn't make the noise until the car started moving. Drove me crazy. Lubed the cable and the problem magically disappeared. BTW, if I had it to do over, I would have just replaced the cable.

 

Cant be the cable cause it gets louder the more i push on the gas.

 

The more you push the gas the faster the car goes which makes the speedo cable turn faster.

 

althought I cant deny your logic, here is the sound, if its the speedo cable i'm gonna be irritated.

 

Well, you never know with these cars, but that's pretty much what mine sounded like and it was the speedo cable. I got mine from 1Aauto for less than $30.

Edit - Here's a suggestion. Unhook the speedo cable and see if the sound goes away. If it does, there's your answer. If not, the search continues.

 

I really can't tell anything from the sound clip.

 

It's prettu easy to tell if it's the speedo cable. If it makes the noise when the engine revs in park then its not the cable. It only spins when the car is moving.

 

hmm... only makes sound when car is moving?

Transmission
Wheel bearings
Rear end
speedo cable
brakes
u-joints


start eliminating items from the list..

AN EXHAUST LEAK WOULD MAKE CONSTANT SOUND WHEN THE ENGINE IS RUNNING AND SPEED UP WITH RPM... so this is not your issue


start looking elsewhere.