Help Please

[davidb]

I just had a lot of work done to my SHO. New Y-pipe, Dynomax cat back, new O2 sensors, ECT., ECT., ECT. Today it started to make a loud ratteling sound from under the car. Sounds like it is coming from the new exhaust up close to the SS Y-Pipe. When I rev the motor it seems to go away. When the RPMs come down it starts ratteling like a can of bolts. My car may be running rich at low RPMs because I am having an on going problem with my secondaries. They are open all the time because of a wireing issue that has not been worked out yet. Anyone have any idea what may be going on with my car?? :banghd: I would really appreciate some feedback.

Could I have killed my new cats? Can they break apart and rattle around in the exhaust?

Dave,
Southren, Maryland

 

[davidb]

Anyone? any ideas?

 

[jaded93atx]

Any loss of HP?, clogged cats would do that, bang on the cats with your fist and try to find the source. If youve been torqueing it you could have loosened the exhaust studs, also check the doughnut gasket and the heat sheild...this really isnt a emergency issue though is it. Your secondaries seem to be of more importance.

 

[ohfosho]

it is most likely the heat shields.

 

[davidb]

Its the cats!

Had the car up on a lift today. Everything is tight. Banged on the top cat and it sounded solid. Nothing rattled. Banged on the bottom cat and it sounded like an empty bucket, but I am getting ahead of myself. On my way to work this morning the rattle I heard coming from the front stoped. When I got to work I could hear the rattle in the back (very loud). Decided then to leave early and take the car to a friend of mine who has a local repair shop. On the way the car ran funny, then al the sudden it lunged forward like it was goosed and ran better than it ever has . What we found other than a hollow cat was that a big piece of it worked its way all the way through my exhaust and lodged it self in my new Dynomax muffler. Hit the muffler with a mallet and it sounds like a golf ball is in there I am taking it back to proteck automotive on Monday. They just put the exhaust in. What happens next is hard to say I guess I'll have to think about running without cats.

Dave

 

[Russsho]

Dave, make sure you clear the debris out of the exhaust system. Bad things will happen if the engine vacuum sucks that stuff in.

 

[davidb]

Dave, make sure you clear the debris out of the exhaust system. Bad things will happen if the engine vacuum sucks that stuff in.

Thanks, will do.

Dave