sipar69 Posted January 23, 2012 Share Posted January 23, 2012 Recently noticed the exhaust makes a metalic rattling noise when the car is started from cold. Seems to die down after a short time and isn't present when restarting the car after a drive. I'm not sure if it's always done this, as I think I only noticed it recently while watching my girlfriend start the car from cold. I know some people in the U.S. have had problems with rattle from the Stillen if the fit leaves it too close to the underside of the car in a particular area, but I would guess that would mean it would rattle all of the time, not just on starting. Is this normal - just to do with the car warming up? Quote Link to comment Share on other sites More sharing options...
Southernspeed Posted January 23, 2012 Share Posted January 23, 2012 It could be rattling just on start up as the engine itself will move around more when cold due to the way engines fire on enrichment. I'd take a look along it's length and look for any very close fitment issues. Quote Link to comment Share on other sites More sharing options...
Chris`I Posted January 23, 2012 Share Posted January 23, 2012 Cant say I've ever noticed any rattling. Looks like fitment/alignment of the exhaust might be slightly off. Just take a look under her and see if you can see where it strikes (if at all) when you fire her up. Quote Link to comment Share on other sites More sharing options...
Lexx Posted January 23, 2012 Share Posted January 23, 2012 Does the Z34 have a chassis brace underneath? Could be the exhaust sitting a little low and rattling off that (same thing happened to me with the RX8). If this is the case, just put some washer spacers in the brace bolts. Quote Link to comment Share on other sites More sharing options...
sipar69 Posted January 23, 2012 Author Share Posted January 23, 2012 Things are going from bad to worse! Took a look under the car with the engine on to see if I could find any fitment issues and noticed liquid dripping from the area shown below. I'm guessing that shouldn't be happening!? Quote Link to comment Share on other sites More sharing options...
Chris`I Posted January 23, 2012 Share Posted January 23, 2012 Depends what the liquid is I guess. There will be some water on cold starts coming through the exhaust, so its probably just that. Does mean the slip joint isnt sealed properly though, so that will need adjusting or redoing. Might also be why it rattles if the ubolt isnt done up tightly? Quote Link to comment Share on other sites More sharing options...
Southernspeed Posted January 23, 2012 Share Posted January 23, 2012 You get a lot of water in an exhaust pipe. It's normal. It's just leaking from the joint. You actually get about a gallon of water for every gallon of petrol burnt. More for Diesel ! (6000 litres od CO2! Quote Link to comment Share on other sites More sharing options...
sipar69 Posted January 23, 2012 Author Share Posted January 23, 2012 You get a lot of water in an exhaust pipe. It's normal. It's just leaking from the joint. Thanks. I'm guessing I need to get this looked at though if the joint is leaking. Quote Link to comment Share on other sites More sharing options...
sipar69 Posted January 23, 2012 Author Share Posted January 23, 2012 Had a good chat to Tom at TGM where I had the exhaust fitted. He reckons the liquid isn't an issue - as some of you have said - just condensation build up escaping from the slip joint and nothing to worry about. The only way to get rid of it would be to use a sealing paste which would then make it impossible to get the exhaust to pieces again. He doesn't think the rattle on cold start is a fitment issue because it would be constant, not just on start up. He thinks it might just be a quirk of my particular set up. I can live with it since it only lasts for a very short time on initial start up. Quote Link to comment Share on other sites More sharing options...
Lexx Posted January 23, 2012 Share Posted January 23, 2012 You could always get yourself underneath the car and get someone else to start it and see if you can locate the source of rattle that way. Quote Link to comment Share on other sites More sharing options...
Chris`I Posted January 23, 2012 Share Posted January 23, 2012 TBH Tom and the guys know their @*!# when it comes to the Zed, fitting exhausts is second nature to them. I think they did Colins and very nearly had mine done there too - got it done at a local place in the end - but TGM fitted the Nismo to my 350z. Very trustworthy. I'd ping Stillen an email. Margaret and the team are very helpful too, just remember they are running behind us in time zone so may take until tomorrow to get a reply. As I say I havent noticed mine rattle, so should be something thats quick and easy to fix. Quote Link to comment Share on other sites More sharing options...
sipar69 Posted January 23, 2012 Author Share Posted January 23, 2012 TBH Tom and the guys know their @*!# when it comes to the Zed, fitting exhausts is second nature to them. I think they did Colins and very nearly had mine done there too - got it done at a local place in the end - but TGM fitted the Nismo to my 350z. Very trustworthy. I'd ping Stillen an email. Margaret and the team are very helpful too, just remember they are running behind us in time zone so may take until tomorrow to get a reply. As I say I havent noticed mine rattle, so should be something thats quick and easy to fix. Thanks Chris. Just took the car out for a quick drive. As Tom promised when I checked the drip afterwards it had stopped. I will send Stillen an email about the rattle but even if it remains an issue I can live with it - soon dies away once the car warms up - definitely not occuring while moving so I'd be surprised if it's a fitment issue. Will post results if Stillen come back with anything useful. Quote Link to comment Share on other sites More sharing options...
Lexx Posted January 23, 2012 Share Posted January 23, 2012 I wonder if it's a lose bolt/connection. Then as it expands when the car heats up it stops. Get under the car when its cold and give the exhaust a shake to see if you can hear anything knocking around. Quote Link to comment Share on other sites More sharing options...
Tarmac@TarmacSportz Posted January 23, 2012 Share Posted January 23, 2012 I would imagine Stillen will ask for an independant report from a garage Simon. Would be interesting to see where it's coming from, be nice if you could get it on the ramp but it sounds like by the time it's up the rattle will be gone. I've had similar issues with things in the past, obviously these types of products are tested vigourously but usually in the companies facilities in California where it's a bit warmer. As Lexx says it could be that the joints are expanding and shrinking very very slightly, not a clue though but I imagine it will completely disappear in the spring. Let me know how you get on and if you require any assistance Quote Link to comment Share on other sites More sharing options...
Chris`I Posted January 23, 2012 Share Posted January 23, 2012 Sure if you ask Tom will whip it up on a ramp when its a quiet time and have a poke about. He rebled my brakes when I wasnt 100% happy with them. Had to do it after they officially closed for the day, but he was more than happy to do it. Quote Link to comment Share on other sites More sharing options...
sipar69 Posted January 23, 2012 Author Share Posted January 23, 2012 Cheers guys - will let you know how it goes Quote Link to comment Share on other sites More sharing options...
The G Man Posted January 24, 2012 Share Posted January 24, 2012 Does the Z34 have a chassis brace underneath?Could be the exhaust sitting a little low and rattling off that (same thing happened to me with the RX8). If this is the case, just put some washer spacers in the brace bolts. This is what it is most likely to be, had the same prob with my set up. The guy who fitted it knew straight off what the issue was. He put an extra washer on the chassis brace nuts and a cure was had. Did the garage get it back on the ramp? If they go along the main pipe, it'll be almost certain to be NEARLY touching, but with the extra vibration on start up it just touches and causes the rattle Quote Link to comment Share on other sites More sharing options...
sipar69 Posted January 24, 2012 Author Share Posted January 24, 2012 Does the Z34 have a chassis brace underneath?Could be the exhaust sitting a little low and rattling off that (same thing happened to me with the RX8). If this is the case, just put some washer spacers in the brace bolts. This is what it is most likely to be, had the same prob with my set up. The guy who fitted it knew straight off what the issue was. He put an extra washer on the chassis brace nuts and a cure was had. Did the garage get it back on the ramp? If they go along the main pipe, it'll be almost certain to be NEARLY touching, but with the extra vibration on start up it just touches and causes the rattle Thanks - that sounds likely because the vibration stops as soon as the engine drops from initial start up to the more gentle rumble once its warmed up. I am taking the car over to TGM on Saturday morning so they can get the car up on a ramp and take a look. I'll mention this. Can you explain in simple layman's terms exactly where under the car this is likely to be an issue ? Quote Link to comment Share on other sites More sharing options...
Chris`I Posted January 24, 2012 Share Posted January 24, 2012 You'll see it easy enough when its on the ramps matey, dead easy to spot where it will be fauling it, theres not much down there for it to touch. Also have you seen this? We're meeting up at Fleet services before hand - viewtopic.php?f=93&t=57180&start=270 - meet thread - viewtopic.php?f=93&t=57773 Not that Tom will struggle to sort it, but a few of us may be able to pop in depending on what time you are on the ramps. Quote Link to comment Share on other sites More sharing options...
sipar69 Posted January 25, 2012 Author Share Posted January 25, 2012 You'll see it easy enough when its on the ramps matey, dead easy to spot where it will be fauling it, theres not much down there for it to touch. Also have you seen this? We're meeting up at Fleet services before hand - viewtopic.php?f=93&t=57180&start=270 - meet thread - viewtopic.php?f=93&t=57773 Not that Tom will struggle to sort it, but a few of us may be able to pop in depending on what time you are on the ramps. Cheers Chris - really appreciate the offer but I've agreed to be there for 8.30 am. I'm guessing that will be a bit early By the way, will the exhaust vibrate more on a cold start than re-starting the car when the engine is still warm? Just wondering why the problem didn't seem to occur when we started up fairly soon after a journey when the engine was still warm. Unfortunate in a way, as is it means I can't demonstrate the problem to Tom. I'm going to try and video the car on start-up to see if I can capture the noise - if I can (might not work on my crappy camera) I'll post a link at some point along with an update following Tom's checks. Quote Link to comment Share on other sites More sharing options...
Chris`I Posted January 25, 2012 Share Posted January 25, 2012 I'd imagine its down to the fast idle when cold. If you hold the warm car at the fast idle revs (around 1k RPM I think) then you should be able to reproduce it. TBH it depends on whats causing it, but something obviously isnt tight enough (perhaps a joint somewhere) or its too close to a cross member or other part of the body. Either way having it up on the ramps they should be able to sort it. I cant see that the engine would move more when cold but perhaps it does, I'd imagine its down to the higher revs at cold idle or one of the joints when it warms up. Remember also that the y-pipe doesnt have a flexi pipe so any movement will be transmitted all the way back to the tips, so even the smallest movement I guess could cause contact somewhere. And yes 8:30am is too early. Would have come if it were just me, but the missus wouldnt appreciate leaving that early! Quote Link to comment Share on other sites More sharing options...
Ebized Posted January 25, 2012 Share Posted January 25, 2012 Cheers Chris - really appreciate the offer but I've agreed to be there for 8.30 am. I'm guessing that will be a bit early But should be just right after having the car checked to give it a nice gentle run over to the Grasshopper to join some 36 other enthusiasts - come on we want to see your motor and say hello viewtopic.php?f=93&t=57180&start=270 Quote Link to comment Share on other sites More sharing options...
sipar69 Posted January 25, 2012 Author Share Posted January 25, 2012 Cheers Chris - really appreciate the offer but I've agreed to be there for 8.30 am. I'm guessing that will be a bit early But should be just right after having the car checked to give it a nice gentle run over to the Grasshopper to join some 36 other enthusiasts - come on we want to see your motor and say hello viewtopic.php?f=93&t=57180&start=270 Cheers Colin - will see what I can do (might depend on how I'm feeling if this bloody problem can't be tracked down! ) I've made a recording of the noise - hope this link works (just click on the black square). You can't see a thing because it was too dark when I got home from work but you can definitely hear the rattle. The rattle subsides just as the engine calms down at about 7 seconds - just before the vid ends. Strange thing is I started the car four times - the rattle only happened on start number two! Really starting to bother me - just hope Tom can track it down. Quote Link to comment Share on other sites More sharing options...
sipar69 Posted January 28, 2012 Author Share Posted January 28, 2012 Spent an hour at TGM this morning having the exhaust looked over by Tom. No obvious areas where it was close enough to vibrate against the car, no loose bolts (they all got tightened, just in case) and no obvious defects in the exhaust. In fact, Tom commented that it's a really well made exhaust. We ended up agreeing that the most likely cause of the rattle is that at certain revs the vibrating exhaust was creating a resonance causing the side panel of the heat shield to vibrate. This is because the shield has a side panel on the right which is very easy to "twang" with your finger. This makes a tinny noise that might account for the rattle. Tom assured me that removing this part of the shield would not harm the car. He dropped the exhaust a few inches and carefully removed it. He then ground off the spot-welds holding the side panel in place and re-fixed the upper part of the shield to the car. Because the problem has been very unpredictable (doesn't even happen on every cold start) it will be a while before I know if its worked, but I'm hopeful........If it's not that then I have no idea what it could be and will probably just have to live with it (only lasts a short time). Even though he worked on the car for an hour, Tom refused to take any money off me until we are sure the problem has been solved! Fingers crossed! Quote Link to comment Share on other sites More sharing options...
Chris`I Posted January 28, 2012 Share Posted January 28, 2012 Good to see its been solved or at least you have a route of attack. Tom and the team are very good so I'd expect nothing less If it does still rattle I'd chase up Stillen and see if they have any ideas. 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.