Tried some searching, but found nothing that helps me trouble shoot this. Wanted to see if anyone had any thoughts.

The noise occurs anytime I back off the throttle and let the engine decelerate the car. It is especially noticeable on 3k+ rpm downshifts (i am properly rev matching).

It is a rattling / slight grinding sound. Seems like its coming from the clutch. If I give some throttle, the sound goes away. I don't hear anything abnormal any other time.

I have a stock clutch, is this normal? any ideas what could be causing the noise?

 

Im thinking your throw out bearing is starting go. Bump for answers i wanna see what everyone thinks as well. Does it make the same noise with no down shift. Like if you take the car up to like 3200 and then let off the gas and let it cost to say 2500

 

Yup it will make the sound if i simply let off the gas.

 

I have the same issue. I have asked prior... some say oil, some say bearing... I have not been able to fix it yet. Almost sounds like the LSD or differential used is having issue. I agree with you on the sound, and that no matter what you do, if the engine decelerates, or you let off the throttle, it reattles and hums. What year is yours? Mine is an 2004 EVO 8 with aftermarket clutch... not sure but think it has a lightened fly as well. I bought mine used, and it had the clutch in it. Then as fast as my revs drop, etc., gave me the idea that there might be a lightened one in there...

I also thought it might be the downpipe. I am uising a 3 inch, and I thought it might be rattling against that cross brace infront of the tranny, that hooks to the inside of the a-arms. This bar runs directly below the downpipe... are we hearing exhaust rattle?

Hope we can finda solution man, drives me nuts, and sounds horrible with the exhaust...lol.

 

i am not claiming to be an expert but if it is only on deceleration there is a possibility that it may be clutch chatter. i have this on deceleration and if you sit at a light with the clutch pushed in it is silent but if you let the clutch out in neutral it should make that same noise but less noticeable. this is usually more prevalent with aftermarket clutches.

 

how many miles on your clutches?

 

dont know how long on mine... I have heard that reply as well. Any chance to get rid of that, or is it with us for the clutch duration?

 

First off, are you 100% sure you have a stock clutch. Not to insult your intelligence, but if you bought it used, you never know unless you take the tranny apart. Obviously if you bought it new, disregard this question and the following information.

This is a pretty common occurrence with aftermarket clutches/flywheels. I too, have had these rattling/grinding sounds upon deceleration (in gear only) after installing my act clutch and prolite flywheel. From the research I've done on here, it's normal to hear more sounds, especially with a lightened flywheel.

 

This is very correct. but it is not uncommon for the stock clutch to make the same sounds how ever it is much less noticable. if you came from a car with no clutch noise and drove the evo it would be very noticable. i came from driving a pos which made no noise what so ever. the evo sounded loud as **** then i put in an exhaust and could barly hear it. after i upgraded the the exedy hd twin i can hear it all the time. but honestly i dont really care it is what it is.

 

I am not 100% sure the clutch is stock. It feels stock, and smells a bit if pull hard in 1st and 2nd, i assume that means it slips a bit. The clutch has at least 40k on it. If it is stock then it has 60k.

I checked the car over for aftermarket parts. Had only an hks intake, electric blue ebrake (fast!!) and a backwards bov. No tune as the maps look stock. The clutch does not feel aftermarket and it doesn't rev like it has a light flywheel.

The exhaust is completely stock, so that's ruled out.

I do hear a difference in noise while sitting in neutral. It is very quiet. If I depress the clutch, the noise dissapears and the rpm will rise slightly, especially during warmup.

 

what about this being a bad throw-out bearing? or maybe the clutch is not completely disengaging?

 

Keep in mind, my ACT clutch (HD street) with the prolite flywheel, feels almost exactly like stock. Initially, during about the first week or two, the pedal was a little bit stiffer but since it has gotten as soft as stock (unless I'm just getting used to it), but if a person has never driven another evo before, they'd have no idea the setup was aftermarket.

The flywheel I installed is almost an unnoticeable difference IMO. 95% of people wouldn't even know I had a prolite flywheel if they drove my evo.


Really though, if you have a stock clutch (as someone else already said), this would be very uncommon to make the sounds you are describing, so it may be something else. The only way you'll find out is to take things apart and see if you are stock or have an aftermarket clutch. Otherwise, you just have to live with it until the clutch goes out and then you'll get an answer.

If it's slipping, you would notice your RPM's climb much faster than normal as I'm sure you'd already know this. Obviously though if you are launching it though and slipping it, you'll probably smell clutch.

Or are you just taking off from a roll in first through 2nd gear and still getting the smell?

 

the quickest and easiest way to see if you have an aftermarket clutch is to remove the inspection door on the transmission. you should at least be able to tell if the pressure plate is a different color than stock like purple for an exedy or yellow for an act. i dont have instructions but if you search i am sure you can find some.

 

Just accelerating from a roll, I have not launched my car yet. It is possible that I just shift too slow.

I'll look into finding that inspection door on the transmission.

My worry is that it is something more significant (transfer case/trans). I skipped a track day because i was worried about this.

thanks for the help so far everyone

 

I have an ACT aftermarket for sure. 12,000 miles since I bought my car used with an ACT in it. Clutch noise two days after the purchase, took it to the dealer I got it from, inspected through the little window, and sure enough, it's an ACT. Hard as hell. I went and test drove 3 other evo's 2 with stock clutches, and another with an aftermarket, not sure of what brand. Mine is still really hard. People who drive my car, tell me how hard it is to drive with this clutch. most people stall it. My revs drop pretty signifacantly when i decel and depress the clutch, which I have read is the tale tell signs of an aftermarket or lightened flywheel, so i thought I had an aftermarket flywheel. Is there any way to tell if you have an aftermarket fly looking through that tranny window? I would realy like to know, so i dont have to pull the tranny apart to tell?