George Lynch

My Z06 vin is 496 built August 30th. The car now has 3,700 miles. The other day the exhaust got noticibly noiser. My investigation found that the butterfly in the exhaust tip was open at idle. After further investigation I found the cause for it being open was the passenger side vacuum hose was disconnected and hanging loose.
I discovered that the bearing, butterfly, activitating mechanism was misaligned during assembly. The butterfly fails to fully open by a few degrees. Also, the vacuum nipple on the actuating pot is misaligned to a point that the attached vacuum line is rubbing on a bumper locating bracket which is what knocked it off.

My question to all of you is: Was this a single incident or is this a common problem?

vegasdude

I have heard of one other similar case where the butterflies were stuck open, but no reason was given........

allanlaw

Forum member out here in SoCal had one side stuck open - I told him to leave it that way because his car really sounded great. We are thinking of designing a mod . . .

spicoli25

I have the switch on the way. It sounds great opened. A switch will let you close it at when cruising at 65.

32valves

great thread title........never thought I'd see the day when that phrase was posted as a serious issue

TicketBait

George, I too have a sticking baffel. (Vin # 00360 built Aug 20th.) I am the forummember allanlaw was refering to in an earlier above post

I have left it that way because I prefer the sound being slightly louder since it is stuck in the open position. But now I am going to get one of LG Motorsport switches so I guess I will first take it in under Warranty to have fixed.

George,Is yours working OK now and which dealer did you go to?

George Lynch

I think I fixed it. It seems that the rubber reducer cupeling was not pushed all the way onto the vacuum pot nipple leaving the big end back far enough to rub on a bracket. I pushed the plastic vacuum hose back into the big end and the small end all the way onto the vacuum pot nipple. This placed the big end in front of the bracket so it wasn't rubbing on it and the plastic vacuum hose, although close, was not touching the bracket. I am going to keep an eye on it to see if any problems develop.

dexter

I'm just a couple of numbers away from you on the VIN and have around 3,000 miles on mine. No problem yet with the exhaust system.

bpf1970

George,

Were both sides open or just one? My exhaust (both sides) has been open for a while now but I really haven't inspected it that closely. It happened during a track event. I'm not sure I understand where you found the problem... did the vacuum hose fall off or did the bracket rub a hole it it?

George Lynch

Both sides were opened(total loss of vacuum in this system). The hose fell off.