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Downpipe Leak Question
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03-16-2013, 02:46 PM | #1 |
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Downpipe Leak Question
I installed a set of PLM downpipes about 2 weeks ago and I think I have an exhaust leak but I am not 100% sure. It sounds like a rattle/hiss. Its only noticeable on startup when the engine is cold and under acceleration. If you have the windows up you can't hear it at all. If you rev the engine while in park or neutral you can't hear anything. I have replaced the gaskets from the DP to the mid-pipes but the sound didn’t change. Could it be the waste gates or turbo? I know it's hard to diagnose without hearing the actual sound but I wanted to see if anyone else ran into this problem. The car seems to be running fine until I get high in the RPM's then it seems to shudder. I haven’t had a chance to sun any logs yet. Any help would be greatly appreciated.
Rob
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03-16-2013, 03:08 PM | #2 |
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probably just WG rattle, normal when installing dps . as long as the car runs fine dont bother......
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03-16-2013, 03:15 PM | #3 |
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Anyway to cure the rattle? Adjustments?
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03-16-2013, 04:22 PM | #5 |
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Can you give a little more detail please? I have a JB4...
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03-16-2013, 04:59 PM | #6 |
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think there is a rattle fix you have to mess around with the JB4 settings...I will have to do the same since Im having my DPs installed in a few
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03-17-2013, 08:05 AM | #7 |
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I am planning on messing with the JB4 settings today. I will let you guys know what happens.
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03-17-2013, 10:07 AM | #8 |
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Changed the future use setting on the JB4 and it seems to have helped a little bit. Still getting a sound under acceleration. I am going to try and adjust the actuator arm. I hope this helps. I hate that my car sounds like a POS.
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03-17-2013, 10:13 AM | #9 |
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Does your interior smell funny at idle? A leak between the turbo flange and downpipe lets exhaust gasses come in through the air conditioning and the cabin smells like exhaust. If you don't smell this then you could rule out a leak.
It does sound a lot like WG rattle from how you've described it. Did you check Youtube videos to see if you can find a match? |
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03-17-2013, 10:20 AM | #10 | |
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03-17-2013, 10:44 AM | #11 |
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What a lot of people find out is that they have a minor wastegate rattle that they can't hear until they get downpipes which make it more audible. Another possibility is that the downpipes are rattling together. I had this happening on cold starts for a while and had to finally crawl under the car to adjust them.
Try the JB4 values if it seems to be helping. If you can't fix it with the JB4 values then you could check the pipes to see if they are touching anywhere. Anything to prevent having to adjust them manually. |
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03-17-2013, 02:18 PM | #12 |
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I also have a noise since I installed DPs on acceleration/load. I don't hear anything on idle or if I rev up in neutral. If windows are closed, I have to listen carefully to hear it.
And yep it is hard to explain the sound.. like rattle/rasp.. I surely have WG rattle which can be eliminated with procede. But if someone has WG rattle, you would probably hear it at idle or when you rev up in neutral and the RPM drops. Also on deceleration. I will change my DPs on Tuesday because they don't fit well.. hopefully it will also eliminate this creepy sound! But I worry that this sound is a normal sound which comes with catless DPs dependably on which exhaust you are using and the conditions of your exhaust/turbos. Which exhaust do you have? |
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03-17-2013, 03:51 PM | #13 | |
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03-18-2013, 09:50 AM | #14 |
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Ive noticed this as well after installing dp's. The best description i could give of mine is it sounds like bolts sitting on top of a vibrating piece of sheet metal or something. I always here it the loudest right a 3k rpm and then i goes away as soon as i get passed that.
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03-18-2013, 10:23 AM | #15 | |
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03-18-2013, 01:24 PM | #16 |
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I wish I knew before installing the pipes. I wouldn't have. I would have spent the money on Meth for when I go to the track. This is just really pissing me off. Car sounds like a civic with crap exhaust.
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03-19-2013, 03:02 PM | #17 |
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Changed my DP's today an the new ones fit much better. But the noise didn't go away.
Did you guys ever tried natural aspirated (N/A) mode? Any difference? Because if I change to N/A there is no difference at all. But if wastegate causes this problem the noise should disappear, right? Or are we talking about "rasp"? Which comes with DPs depending on which exhaust you are using. |
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