Noise during acceleration-99 prizm

When I accelerate it sounds like I have an exhaust leak coming from the engine...but only when I accelerate. My pipes look OK and if I rev the engine out of gear it sounds fine. I think the intake manifold is OK since I have no coolant loss....Any thoughts.

I also have codes P0446 and P0441.

Thanks for the help.

Got the same condition. The noise goes away once the engine warms, but snow or rain will cause it to come back. I heard its caused by a crack that developes in the exhaust manifold, or manifold gasket. Good luck with the evap codes....all 99's develope them. It's either the pressure sensor or the canister

p.s. also make shure the exhaust system heat shields are tight

Update: I got the car checked out and they said the sound is caused by a leak between uppipe and exhaust manifold and can be fixed with a new donut gasket/bolts/springs. The engine torque causes that joint to flex causing the sound. estimate=$100-150.

Update: I got the car checked out and they said the sound is caused by a leak between uppipe and exhaust manifold and can be fixed with a new donut gasket/bolts/springs. The engine torque causes that joint to flex causing the sound. estimate=$100-150.


Seems kinda steep for gasket replacment. Have you tried a muffler shop?

I have a 1999 Prizm, I just needed a bolt for mine $9? Then 1hr labor $75 to replace it on the front exaust gasket flange.

I have this issue again, I found a nice thread about it here: http://www.corolland.com/forums/index.php?showtopic=17057

I just managed to change my serpentine belt in my 1999 Prizm, so maybe I'll take a crack at the donut / gasket.

Um yeah, so I jacked up the car I realized that I had ordered the gasket parts for the down/up pipe to catback (http://www.flickr.com/photos/22325144@N02/2283910623/).

But the issue is likely the connection from the manifold to the up/down pipe. (http://www.flickr.com/photos/22325144@N02/2284699034/) Which has the spring loaded bolts, and is fairly hard to get to (unless I imagine the car is on a lift. I think I'll leave this to the pros.