I picked up my Evo X MR a couple weeks ago, it had about 6k miles on it and had an AEM intake and a Magnaflow exhaust when I got it.

Ever since I picked it up I noticed a "rattling" noise coming from the valve area, it happens at idle and doesn't increase with RPM, it sounds like a bracket loose or a exhaust leak near the turbo but doesn't seem to be either of those.

I remember my IX MR making similar noises at idle and that it was a well known 4G63 thing to have some valve noise at idle, I was just wondering if this was still the case with the 4B11T.

- Patrick

 

One of my sponsors MR had this odd rattle that sounded like it was coming from the lower valvetrain area. Turns out that it is likely the SST transmission making some extra noise but we never really determined 100% what it is. It's possible that it adds some knock counts into the mix but it hasn't shown up as a major problem. Probably a poll amongst MR owners will determine if it is common for the SST tranny to make some extra noise. It almost sounded like a spun bearing but if that were the case we would have seen damage long before now with all the track use and noticed problems when draining the oil. His engine compression was around 150 across the board and it made 360 whp on a Mustang Dyno at 26 psi.

 

Yeah, it sounds a lot like knocking or like valve tapping. But it only happens at idle, everything is smooth once you rev it.

SST noise would make sense, maybe some kind of valve or something for the fluid is making noise.

 

Like this?

https://www.evolutionm.net/forums/ev...ing-noise.html

 

Yep, that seems like exactly what it is. So no worries then?

- Patrick

 

yeah, i mean i've had it now for 2k miles and so far so good. what's really strange is now that it's summertime and i'm driving the car in this heat, the sound seems to almost completely go away when the car is really hot... idk?

i've heard it's the evo's valve train noise, a bent tappet, exhaust leaks, etc. it doesn't seem to affect performance however as i'm now running a stage 1 tune and have made multiple WOT passes since i found the noise.

if it makes you feel any better, i've found about 5-6 other videos on youtube with the same tapping noise. i can find them for you if you want me to. shoot me a pm and i'll look for them...

best bet would be to take it to Mitsu and get it in writing that you know the noise is there, and are having them check the car out. they'll most likely come back and say it's ok and give you the necessary documents showing you brought the car in. that gave me the peace of mind to go ahead and just enjoy the car

 

i know the sound you're speaking of here... sounds like a low-pitch thud almost. another MR owner on Evox had this and actually got it fixed. i don't think it was anything catastrophic, more annoying than anything else. something to do with the sst i believe.

this is a different sound than OP is suggesting btw.

 

I had that annoying sound/ rattle. Dealer got it fixed. Cause: tensioner pulley has a bad bearing!