I did attempt to, but of course, I couldn't get it to rattle. I think the car needs to be fully warmed up. I'm going to try again after work today since I'm normally in traffic and sitting.

 

nobody from comptech returned my call, wahh, guess i'll have to bug them again

 

howd it go moda?

 

Couldn't reproduce it. Closest I could get to the sound is holding a rev at around 2500 RPM and it sounded like a harmonic from the header (i.e. the pulses from the exhaust gas made the header emit a harmonic noise).

I looked at everything from the top of the header to the back of the cat and everything looks PERFECT and in excellent condition. I wish I had better news.

 

bad news, i talked to DrkAngel348 and he said the mod he did to the hangers really didn't get rid of the problem

 

talked to Bill at comptech, he had never heard of this issue before, so if more people called it certainly wouldn't hurt. he also said i can send it back to them and they can take a look.

 

just installed my comptech header today at the shop and it rattles pretty loud when car is stopped with a gear in drive. rattle goes away when i shift it into neutral and comes back when tranny is engaged. i hear this rattle even with ac off. so no real solution for this yet huh??

 

^^^ Wow and I was considering this to be my next mod... hmmm... I think I'll have to wait on this.

 

At this point, I'm not sure what % of us are having this issue that own them. I know I hear a harmonic resonance, but I can't consistently reproduce this. I'm hoping someone who can consistently reproduce it can track it down.

 

if u have this issue please call comptech as when i called they said i was the first person to say this

 

mine is a pretty constant rattle and it sounds like metal to metal rattling. i'm gonna go back to shop today and get it on the lift to track this crappy noise. hopefully its a easy find such as random cat banging on my cusco t2 brace...

so how long did you guys took after the installation to hear this rattles? some say it could be the torn rubber hangers, but mine started to rattle as soon as header got installed.

 

mine rattled as soon as i got it installed, only happens when car is not moving, and in idle and have AC on. also only happens at certain times with the AC on, it is not like 100% of the time.

 

I know that we have good evidence around it being header area related, but has anyone proven it is the header (i.e. a firewall rattle, etc).

I wish someone could reproduce it and pinpoint the area where it happens. I tried for 5 mins and now I'm I can't make it happen. Don't know which is worse, not being able to reproduce it or actually knowing it is there and just can't hear it.

I'll try again today, but I haven't gotten it in a long time, but then the temp has been very cool here in Ohio and don't know if that plays into the mix or not.

 

i have not had a chance to bring it back to the shop that installed it to have it duplicated while on a lift, i will make sure to report back when i do

 

mine rattles whenever car is stopped with gear engaged in drive. i'm gonna head to shop right now and hopefully they have time to check it out.

 

your issue sounds worse than mine, maybe due to you having an AT or maybe totally different issue. who knows

 

i just came back from the shop and i think this is the noise we have to live with. heat shield, cusco lower brace and any other places that could produce rattling noise have good clearance. he also said he had to pull the exhaust a little closer to the header because of its shorter length, but nothing was hitting on the components. we just suspected that it could be the torque screw (bolt with springs) that is not used on the comptech header.

it was definitely louder yesterday, but now it only rattles when the ac is on.. its sure annoying when the weather is hot and ac needs to be on.

 

please call comptech and report your issue than

 

ask for BILL in the tech dept.

 

i just called and they say i'm the second person to call about this issue. they say to send it back so they can check what is the issue with this rattling noise.

more people should call comptech about this noise and let them know so that they'll fix this rattling issue.

 

The next time I hear mine, I will call. I swear, I'm listening every second I drive my car for anything now.

I think it is also worth mentioning too, I love my header still.

 

This thread is funny cause i had this problem from day one and even posted about it, but the thread never grew. My rattle feels more like a vibration rattle and it is most apparant with the AC on.. However, I do get it sometimes when i'm idling in "D" with the AC off. I have no clue what it could be, and the exhaust hangers are good.

 

Can someone please get their significant other to sit in the car and replicate this so we can pinpoint it.

 

its really hard to replicate the rattle while its on the lift. somehow it goes away while going up the lift. everyone with this problem should start notifying comptech and let them find out the problem. its just time consuming and money wasting for us to do it.

 

I was thinking more about it being on the ground, hood open and trying to locate it that way. Don't worry about the heat, just find that rattle.

 

So is there a stronger replacement part for that #9 like exhaust hangers JTso found? I'll try replacing all the hangers and see if the rattles go away.

 

Im get part number 9 replaced on monday ill tell you if it fixes the rattle.

 

probably not. mine doesn't have any wear and tear but it still rattles.

 

The mechanic saw it and said mine was torn due to the size of the header, is differnt so it wasn't really holding it like stock.

 

Here are some pics I just snapped of my Header hanger. I don't see any issue with mine.

 

clearance is good and bushings are good also. if we can find a way to reduce excessive vibration after turning on the ac, it will difinitely reduce this noise. could this be caused by missing extra support that stock header has on the upper portion?

 

I have a rattle sound right now with my stock header but I believe it is coming from my cusco type 1 lower strut bar hitting my cat cause my lower strut bar has turned into a skid plate and since been bent slightly with my car being so low. It only happens sometimes when I come to a stop with the car in drive and my a/c is always on. If I shift to neutral it stops which leads me to believe it is related to the same problem you guys are having. I mean obviously when the engine is in neutral there is less vibration so that is why it goes away however in drive the virbration is sent through the exhaust. I still think I am going to order the header cause the sound only happens in drive when I am stopped and I have just been shifting into neutral at those times anymore and it has become second nature to do so now.

 

Considering there is about 4-5 of us reporting this rattle, mine being totally inconsistent, I still think the Comptech header is great buy.

 

I'm chiming in...

I've also been having the same rattling issue since day one of my Comptech headers (and exhaust) install. I put my car on jackstands this weekend to take a look myself at what could be causing this annoyance. For a bit I thought it could be something as simple as the heat shield hitting the frame, but that didn't seem to be the problem. My guess is that the headers cause a lot of extra vibration, and when the AC is on, and/or the engine RPMs are low, all that added up makes something unrelated to (but located near) the headers shake around causing a rattle. From past experience I've found that it doesn't take much metal to metal contact to cause a rattle, and sometimes the cabin of the car can amplify that sound (hence why you can only hear the rattle from inside the car).

Anyway, this may be a problem we'll have to live with, but I definitely will be continuing to try and find a solution. In the mean time, I'll give Comptech a call and inform them that I'm another person with this problem.

 

What RPMs is your guys car idling at with the a/c on?
When you get the rattle, are the RPMs fluctuating, are remaining steady?

I think minkl81 might have a good idea. He mentioned that it could be because with the aftermarket headers, we are all removing the spring loaded bolts that are on the OEM header. Comments?

 

my RPMs are fluctuating when this happens, i agree that i think the comptech headers do not dampen engine vibrations as well as the oem ones which is causing resonance to emit through the engine cabin.

i am curious whether JTSOs Engine torque dampener mod would reduce this shaking/vibrations as low RPMs

 

what i dont think will help is sending the part to comptech, i doubt that visual inspection will solve the problem. i think its something that they would have to hear while sitting in a car that suffers from this

 

i believe this is caused by excessive vibration after the comptech header install. not much cushioning is available with comptech header since spring loaded bolts are gone and also i belive stock header had a bolt on point on the upper portion of the header that could reduce the vibration.

this is why some of the guys were able to eliminate the rattling by extra grounding. i just did a groudning on my car too and it really smoothes out the idling, but not enough to kill the excessive vibration after the ac is on.

i just thought that JTso's ETD might eliminate the rattling too. hopefully he makes one for the cusco strut bar too.

 

Read this whole thread and just offering some pointers from our experience with JDM Euro R :

1. CUSCO 4 point under brace bar is located too close to the cat cover. Clearance about 5mm to the edge of the cat cover. Any rattling here is done when the engine vibrates especially in low rpm or sudden acclerator release.

soln : bend the brace back using a crow bar. carefully select a leverage point when you do this when car is raised up. A real pain due to a design error.

Next : Locate the front centre hook and put a rubber so as to raise the exhaust higher. This also helps to reduce the vibrations.

2. AC on and the vibration start with the header installed. I think the header has no flexi pipe connection for the 2-1 location. So, this will definitely increase the vibration on the whole cat to cat-back.

We also experienced that AC unit from japan as not reliable and some has had the AC unit broken. We suspect that it cannot keep up with the high rev at 8200rpm range. Furthermore, the AC units seem to lack a AC lubricant and we are now pumping in the lubricant to hopefully improve it from breaking down.

The AC could also give a rattling sound like when it is about to KO. Sad, but true. Maybe we are using different AC compressors, but some of us found out the hard way.

3. The exhaust chart : Use Polyurethane made to replace part no 9. This has 3 pieces, 2 located to hook each exhaust at near end of the bumper. The 3rd piece is located at the centre of the car. I think the CL9 and the CL7 auto has another holder location and replace this with polyurethane as well.

Polyurethane is much more firm and does not wear down like rubber. We see HKS and Fuji aftermarket exhaust swinging left to right. Thus, replacing these 3 rubbers shoudl solve this issue.

Tomorrow, i will be doing this. I also need to raise my Fuji a little as the CUSCO is rattling again. I will also see how to repalce the front end rubbers with polyurethane. Price is less than US$5 / piece for the No 9. Comes in red colour or blue. There is also a longer version that cost more, but I cannot recall for my car. I know the shorter ones can replace part 9.

Last guess on the after market header rattle. Don't be surprised that if there is no 2-1 flexible hose, it could be the whole exhaust vibrating and magnified. Also possibly the heat shields are adding to some vibrations from the total exhaust moving. My best guess is to repalce some of the part 9 and also further up front rubber.

Hope this helps. I also get irritated with rattles...drives me nuts..
Well,

 

just bend your cusco bar back to normal.. worked for mine