VIPNiSS

I noticed my exhaust is shaking thus causing a weird sound when I accelerate hard cause of the vibrations. I have a fabspeed exhaust system I had them install but I also had them cut out the secondary cat and weld on a replacement pipe. Not sure if that caused this issue.

The exhaust shop told me it seems like it's my car having a slight misfire. No check engine codes or anything. It has 90k miles and I did literally just replaced the coilpacks today cause they were all cracked. I figured that might of been the issue but still doing the exhaust dance lol

VIPNiSS

just found out my crankcase check valve has a vacuum leak. I wonder if this could be causing a slight mis and making the exhaust shake like that? ordered parts already.

nodoors

Mine does not do that. Yes, vacuum leaks can cause a rough idle like that. How did you diagnose the check valve?

VIPNiSS

When I bought the car and did a pre purchase inspection the dealer told me the crankcase check valve would need to be replace down the road. They advise you can hear a small hiss. I did some research and read somewhere to open the oil cap with engine running to check for leak. When I open the oil cap you hear really hear it hissing.

John@Fabspeed

That engine definitely is not running smooth my friend, hence the dance. Best of luck with the diagnosis and repair! Can always smoke test the vacuum system for leaks, most shops with have the tools to do it

Sniffer

I don't see any hangars holding the exhaust in place?

From memory mine has at least one set per pipe, might even be two

VIPNiSS

sniffer thank you very much for the input. You were right on the money. When they cut the secondary bypass and welded a straight pipe the hangers were gone. They made new hangers for the pipes and welded it. Issue is now fixed. Thanks everyone