Ideas on what this sound may be? PLEASE HELP!

Ok so basically I've got a 1995 Vti-R and something I've noticed since I bought it is that when you hit about 3100RPM and up through the rev range you can hear a feint sort of buzzing/rattling sound coming from the engine/gearbox area, this sound seems to be less audible when the car isn't moving and in this case can only really be heard when the revs come back down sometimes, even while the clutch is pressed.

It sounds like it's coming from the passengers side of the engine bay. The strange thing is you can only hear it from inside the cabin...? My engine is running good and hasn't got any problems so I don't think it's anything serious, it's just annoying and I'd like to get rid of it.

So, anyone got any ideas or has anyone else experienced this?

sounds like ur CAT converter its rattling inside

Check your Pannels, tap your door and see if it rattles, tap your passenger side pannel and see if it rattles.

This recently happen to mine and it was my passenger side pannel, i had to tighten it up abit.

Yeah I'll check that out, although it's hard to believe that if it was a panel or something, that it's only buzzing in a certain rev range and not during vibrations from the road. (my car's on buddyclub coilovers so it's a pretty stiff ride) Thanks for your input!

And in terms of the cat, that may be a possibility, but when I had that problem with my DA I could clearly hear that it was coming from under the car and not from the front. Worth a check anyway, thanks!

I'm also gonna try see if I can lube up the engine pulleys somehow, I was thinking they might be a possible cause, any ideas on what would be good for that? WD40? Lithium grease?

Correct me if I'm trying something stupid haha.

Might be checking out your exhaust connections because as you know when you rev the car the engine tilts back and if the connection isn't even on all sides you will notice it. Other than that get your valve clearance check and adjusted? Really depends on where the sound is coming from, higher in the engine bay or lower? and does the sound follow your revs.

Check your header mounting bracket hasnt broken.
Its the one at the back of the header (collector).

hey champ is your air box open by any chance or have u got a pod filter or anything...ive got a similar noise around 3000rpm mark which come frm my airbox

oh, yeah man i don't have the top half of my airbox, the car came with it off when i bought it, could this have something to do with it?

thanks guys i'll check these things out for sure, although i thought about the valve clearance, and it wouldn't make sense because it's coming from one side and you can't hear it from the outside or even when you stick your head in the engine bay for that matter.

i am almost positive i have the same prob. best sources always told me it was either the CAT or rocks in the exhaust. i just haven't paid to have it all replaced/checked. turn up musack and u won't here it :D

i had that sound as well. rattly sounds when using too much torque.
when i got my timing belt changed from Honda, they adjusted a few things as well and sounds went away.

It's difficult to know what it could be without hearing the noise.

Knocking/rattling noise

My CRX had a noise that came from the gearbox and it was just a small bearing that had worn down inside the transmission. My first CRX was a bit noisier and it was a bigger bearing in the gearbox that was worn down. However, if you're getting the noise while not moving and with the clutch in then it shouldn't be the gearbox.. It could still be a clutch thrust bearing or something..

There are some harmonics associated with a lot of hondas, it's only minor normally but they do feel busy at times..

I hope you manage to find someone to help mate.

Ok so after having a good listen, i think you guys may be right in that it's 'probably' the cat converter or possibly the same problem my DA had at one stage, which was the resonator. it sure seems that way now, so i'm trying to track down an affordable catback system and a high flow cat, wanted to get xforce but am not having much luck finding a place to buy it from, last guy i checked with said it was out of production. reason for this is that i don't wanna waste money on another stock part when i'm gonna eventually buy a sport exhaust anyway.

anyone know where i could get a decent catback system that wont rape my wallet?

thanks for all the help thus far!~

I wouldn't be surprised if one of the heatshields above the exhaust has come loose.

Hmm ok well I've put a whole new catback on the car, removed the main heatsheild (I had to do it to get the exhaust on anyway), checked the cat converter while it was off the car, tightened everything and the sound is still there, I'm pretty certain it's coming from the engine bay, or at least close to the firewall. I took the car to a honda specialist and took him for a drive, he reckons these cars make plenty of strange noises and it's only natural so it's nothing to worry about. he sprayed some stuff around the belts to see if it'd make a difference but it didn't. It's still doing my head in! I've searched the engine bay for any loose objects and tightened lots of bolts and still has no effect.

I STILL can't understand how it can be so audible but only when you're in the car with all the windows closed. Stationary or moving when the windows are open, nothing. even when you stick your head in the engine bay and rev it, nothing. Not even a mechanic could figure it out! WTF! (and btw it's definitely not the windows vibrating cause it's coming from the FRONT.)

Rep and serious respect to ANYONE who can provide me with a working solution to this because I seriously do NOT want to take my car to somewhere like honda and have them strip my engine apart trying to find it and charge me $100000000 for it.

Thanks.

had the same problem mate and it turned out to be the inside of the header where it joins on to the cat. Just wear and tear unfortunately. So i ended up upgrading the header which then started a chain reaction in mods :)

Do you have a shortshifter installed?

Hmmm, well that would be a likely solution Integra11, but I've already disconnected the cat from the header when I put the exhaust on, and I refitted the cat to it with a bit of silicone to help seal it. so I guess it depends on which part of that connection was vibrating on yours?

And no I don't have a shortshifter currently.

Ok so I took off the heat shield on the headers and it didn't make a difference, so it's pretty much narrowed down to noisy valves (which I highly doubt) or something to do with the timing belt, tensioner pulley maybe?

Gimme some feedback, has anyone else heard of timing belt tensioner pulleys making a rattle, or just generally being noisy? 'cause some peoples threads in the accord forum were about this sort of thing and replacing that part apparently fixed it.

Either way it's seeming like it's something I won't be able to do myself... Which means I gotta cough up more money. :(

Thanks for all the help so far everyone.

Super DA9, on your first post you did say it sounds like it's coming from the engine/gearbox area and then you said it sound like it's from the passenger side??? The engine/gearbox area is on the driver side. SO where's the sound coming from?? Driver side or passenger side????

Well by that I mean engine bay and surroundings, but I did think the gearbox was on that side, well maybe I'm just trippin. It sounds like It's coming from where the belts are on the passenger side of the engine.

But man it's confusing for me too because the only way to hear it is to be IN the car with the windows closed. :S

It possibly could be some rattles in the car itself. All the hondas i've owned seem to have rattled so much it's not funny

this worked for me but may not work for you; i can't say for certain.

i also have a b18c vtir motor and i had that noise as well, which apparently is quite common amongst this particular engine.
i just lived with it and i'm grateful that i no longer have this noise.

like integra11 was saying, it could be the join at the header flange.
every part i changed, i would rev it slowly to the rpm range to see if the sound still existed.
i noticed that when i changed my header, the sound was gone. who knows, could even have been the exhaust manifold gasket
slapping between the manifold and the head.

but all in all, that is what solved my problem.

best of luck in fixing this problem

thanks mate, yeah headers are next on my list anyway so we'll see how that goes. It really doesn't sound like it's coming from under the car though. :(

Ah-ha! After doing some research and talking to a guy that knows about honda's today, I have a strong theory that it's the timing tensioner pulley. I don't suppose anyone knows of a DIY on replacing this part?

Look guys I'm sorry for bringing this back but holy s*** I really need help this is driving me NUTS.

Things I've done:
Fit cat-back exhaust with new resonator
Tightened the S*** out of the flange at the bottom of my header
Removed all heat shields from cat, header and above resonator
Looked around for anything loose under the dash
Applied new silicone sealant to the header gasket (which is still good)
Lubricated the belts pulleys
Found that the top timing cover was missing the two bolts that hold it in, and put new ones in
Looked for anything loose in the engine bay, there was nothing
Asked mechanics and none of them had any idea

Yesterday I handed my car over to a workshop that specializes in japanese cars for them to have a go at fixing it, they told me they adjusted the tappets and checked all the belts and things in that area and around the timing belt, apparently the idler pulley was a bit loose and the bearing was noisy, so they replaced the bearing and tightened it back up. (although on the receipt it said "R&R A/C tensioner pulley and replace bearing") after this they said they couldn't hear it anymore, and this morning when I drove my car I couldn't really hear anything, but tonight I noticed it was there again, only now instead of starting to buzz at 3000RPM it's doing it at around 4200RPM and is a bit quieter. So whatever they did it affected it somehow. I'm not sure if it went away and came back after a bit of driving or if I just didn't notice it till tonight.

I've been told that sometimes it can be the tensioner pulley for the timing belt, so I bought a new one and supplied it to them, however they told me there's no way a tensioner would fail till around 200,000km on the clock, and when they finished the work they said the tensioner seemed fine.

When the sound begins around 4200RPM it's starts like "bzz.. bzz..bzzbzz.." and then 4800-5000 is just "bzzbzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz" all the way up the rev range. And you can't hear it from outside the car or even if you stick your head in the engine bay and rev it.

I've been told many times by mechanics and others not to worry because it's not affecting the engine at all, but I know its not normal! and I really wanna get rid of it! :(

ANY help would be so much appreciated and if there's anyone in ACT who could come look at it please tell me!

stats on my car incase it helps:
DC2 VTi-R 1995 B18C2
ODO: 134,XXXkm
Doesn't burn oil, smoke at all, and no power lag or anything.
I've been very nice to the car, never had my foot to the floor in the 4-5 months I've owned it.

don't go to mechNICS on this, they are just gonnA SAY WHATEVER AND MAKE YOU FORK OUT FOR IT.

yeah thats right, I don't want to but I've been stuck on this for months and I don't know what else to do to solve it.

Hi Super-DA9, I think I may have the same problem as you. I've been meaning to video clip my noise and post it here for sometime now, just been busy with stuff. Anyways can you post a youtube clip of the sound? Mine comes on at ~4000 rpm carries right through to ~6rpm and then dies to the redline. A mate of mine who knows his cars says it could be a loose bearing and that I should live with it. I'm going to try and post a clip soon and don't worry I've done just about what you have trying to figure this problem out.
Valve clearance adjusted = no good
Exhaust flange rewelded = no good (exhaust guy said that it was an internal engine problem)
Done tests and its not a transmission thing, purely engine for now.

I just hope this problem can be solved because it is driving me crazy everytime I vtec her.

It's good to hear I'm not alone here, yeah I agree, it's so discouraging to rev up your car when there's that f***ing gay noise up the top half, and ruins most of the fun in driving it.. :(

I'd take a video but I'm fairly certain the camera's microphone wont be able to pick it up over the exhaust sound. I might give it a shot anyway.

Also mine's dropped it's starting point back to 3000RPM. It seemed gone when I got it back from Advanced Tech Automotive, but then it's gradually come back with a day or two of driving it. The only things they told me they did was adjust the tappets and replace the bearing in the A/C tensioner which was apparently a bit loose, tighten it back on + re tension belts and piece it back together, so I thought the A/C tensioner must have shook itself loose again because tappets don't just change their clearances in a day or two, so I took it apart myself, took out the tensioner and it was still fine..?! So now I'm REALLY confused.

I doubt it's a structural or major issue because my car is performing fine and normally, but it's so @%#$@ing annoying!

If you discover anything more on this, don't hesitate to share it with me, as I will let you know if I find a fix for it or anything that helps. :)

I've made a brief list of other things that could possibly cause a noise like this, some thing are doubtful but anyway here's some of it, let me know if you think any of these are common/likely or whatever.

• Injectors tapping due to being clogged
• Clutch buzz from the thrust bearing (although this is unlikely as the car still makes the noise when the clutch is in)
• Metal header gasket buzzing against the head (also unlikely as I've removed the header and re-fitted it with sealant on the gasket)
• Exhaust leak from the header area (I can't see any cracks or holes though)
• Crack in the header mount (someone had a similar problem with their prelude and said this was the issue, haven't had a REAL thorough look at mine but it looks okay)

If anyone comes up with ANY idea's even if they're super unlikely please post!

Hey dude,
I've know your pain, having to push vtec every now and then to keep the engine fresh, but being too scared cause of that stupid noise afraid you'll be doing more damage to the car. Sorry I haven't been too attentive to this problem, it's just that I'm in the process of getting my car ready for a respray, sick and tied of driving around with body filler by now ( I know 9 months is a long time, been busy can't help it). Anyways here is list of things to check for
*Exhaust flange before the cat converter, make sure that seal is even all round because as you know when you rev the engine, it tilts back and causes an exhaust leak
* (most likely my problem, but haven't had the time to check it out) Camshafts warped or damaged, no matter how many times or the clearance you give your valves if the camshaft is no good the clearance will be off no matter what. Also could be a flogged bearing.
* Vtec rocker arm warped and damaged as above the same thing, replacing either of these is not going to be cheap either way.

Other than that I'm basically blank for ideas. I'm going to get it checked it out Honda specialists here in Perth when I get a bit of time up my hands, but one thing is for sure don't every trust your car to OEM Honda, cause they will most likely get an apprentice to work on your car...

I will post my findings as they come.

Yeah, I wouldn't go OEM unless I had NO other choice. hmmm, well it really sounds like a spun bearing somewhere on the belts side of the engine, but I've checked all the belt pulleys except the alternator. got my car booked in at advanced tech again on thursday so I'll ask them to check that out while they're at it.

I'd think it'd be more of a knock if it was something bent or damaged internally but I'll ask them to look at my cams too.

The noise seems to get more audible and starts a bit earlier when the car is at running temp or after a hard drive. When the cars only just warmed up to the first line on the temp gauge (which is what I let it warm up to every time I drive) it's barely noticeable for the first 5 minutes or so of driving unless you rev it up. Not sure what that could mean but it seems temperature reliant too.

In any case I'm praying to find out exactly what it is on thursday, and I'll post up the details when I get the car home.

speedo cable's grease has dried out? i had a da9 that sounded like a nest of baby birds lived behind the tacho.

yeah my DA had the exact same thing, only problem here is that DC2 doesn't have a cable and the noise follows the RPM, not the speed. :(

Have you ruled out a transmission fault as well? A friend of mine said it could be transmission related however that was quashed when I revved it in neutral to still find the noise, yea its weird how the noise follows the rpm and only in mid range.

yeah it's still there when I'm in neutral too, and pushing in the clutch doesn't make it go away. :(

UPDATE: got my car back from the mechanics today, I don't think they even bothered with anything except a quick "look". so I'm quite disappointed and I'm not even gonna bother with mechanics anymore, around here they're all lazy and don't do good work.

However I did get one piece of information, they said it's a possibility that the water pump or a part of it is making that noise. (they said they didn't have enough time to take off the timing cover to inspect it, but they had my car from 8:30am to 6:00pm.)

This may be true, and while I'm at it (if I can even find someone who can help me do this, hardly anyone knows about hondas in canberra) I might replace the timing tensioner as I have a brand new one sitting on my desk anyway.

Has anyone heard of water pumps playing up/failing and making noises like a spun bearing? :S
...

Revelation I was driving with my car window down the other day and decided to jump the line at the lights. Anyways I noticed that the sound was favouring the driver's side of the engine, it might be me but I think you maybe onto something with the timing belt and possibly a loose bearing somewhere in the vicinity. Hope that helps, further investigations to follow.

lucky, lol. I can't hear the noise in my car if the windows are down. but yeah I've been thinking it has to be something in that area, only problem for me here is that to get the timing cover off is a BIG job, involving removing engine mount, harmonic balancer etc. :(