Stroudy Posted April 15, 2011 Share Posted April 15, 2011 Hi all. Have a Nismo cat back exhaust and on tonights run it just isnt sounding right. As you prob know with the Nismo you get a very rorty bark from the pipes when pressing on but tonight, straight out the garage, it sounds very flat and of standard exhaust note (no offence meant to anyone with standard pipes ). Also, after giving it a bit of boot, it smelt a bit off egg in the cabin (no beans for dinner though). I noticed this smell on the last few runs but the noise was ok then, tonight its just lost its note. Car has only done 36k/4yrs old so i'd be suprised if the cat had gone but maybe theres issues with the Zeds cat I dont know about? Also heard a small metallic knocking sound coming from the exhaust as it moves under power and off-throttle recently but assumed this was just movement. If anyone can suggest anything, before i take it in to be looked at, i'd very much appreciate the help. Cheers, Stroudy... Quote Link to comment Share on other sites More sharing options...
Zugara Posted April 16, 2011 Share Posted April 16, 2011 Sounds like you may have a baffle loose within the system. Quote Link to comment Share on other sites More sharing options...
Stroudy Posted April 16, 2011 Author Share Posted April 16, 2011 Found this on 350zmotoring.com: **In Nissan's quest to build a powerful yet comfortable sports car, the motor mounts on the VQ35 engines were softened a bit. The result is substantial movement of the engine under hard acceleration and deceleration. And since the headers, test pipes, Y-pipe, and exhaust system are connected to the engine they are subjected to these stresses as well. End result? We are seeing a lot of cracking / fracturing of aftermarket exhaust systems - usually around the Y-pipe or the test pipes. Sometimes the cracking is not severe - just enough fracturing for some exhaust gas to escape (thus the hissing). I know I've personally been through 3 test pipes on my Z, especially after aggressive (track) driving.** Does anyone know if this is a well known thing on our forum? P.S - sorry for posting this thread in 3 sections but if a big prob I need to try and get it looked at asap so a bit of saturation posting done.. Quote Link to comment Share on other sites More sharing options...
Zugara Posted April 16, 2011 Share Posted April 16, 2011 have you tried blocking the tail pipes to see if you get a build up of pressure? If you dont, this will indicate that you have a fracture somewhere, if you get a pressure build up, your system is ok. This is the easiest way to check for any escaping gasses, not unless you can clearly hear it Quote Link to comment Share on other sites More sharing options...
Stroudy Posted April 16, 2011 Author Share Posted April 16, 2011 ...just jacked car up then took it for a run. Heres what I observed. - I blocked the pipes up and there doesnt seem to be any pressure leaking from back box to cats (no blowing heard). - The cabin stinks of that cat small (egg) after a few high rev gear changes up to speed. - The usually rorty/howly exhaust note from the Nismo pipes is now muted. - The car feels a little bit down on power, not much but just a bit. Any thoughts?? Will call a garage specialist on Mon morning but if its screaming as a known prob it would be great to know. Thanks.. Quote Link to comment Share on other sites More sharing options...
Stroudy Posted April 17, 2011 Author Share Posted April 17, 2011 Would i get a dash warning light if cat has failed...? Quote Link to comment Share on other sites More sharing options...
Zugara Posted April 17, 2011 Share Posted April 17, 2011 Would i get a dash warning light if cat has failed...? Dont think so, but you would get one if the Lambda sensor fails Pretty sure if you can smell "eggs" in the cabin, you must have a fracture somewhere, Have you had a good look under the car at the entire system Quote Link to comment Share on other sites More sharing options...
Stroudy Posted April 17, 2011 Author Share Posted April 17, 2011 Yeah jacked it up yesterday and had a look underneath while running, also bunged the pipes up at the same time but didnt notice any leaks. Need it up on a ramp to have a proper look though as couldnt get right under at the front.. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.