Ok, I don't know if anyone remembers but I posted a previous thread that my EVO shakes and makes a rumbling sound around 80 mph. It also started doing it in 3rd gear around 3000 rpms. This all started after I got a Exedy Hyper single put in. I took it back to the mechanic (who is the EVO mechanic at the local Mitsu dealer) and of course it would not make the sound. As soon as I left, when I got on the interstate it started shaking and rumbling again.

Also, for the first time, when I was in 5th gear around 70 mph, I pressed the accelerater pretty firmly and the car just violently jolted. The bov released the air pressure, I shot forward in my seat it was so sudden. It did it 2 more times on the way home. Only when I get on the gas aggressively did it do this.

Does anyone know what might be the 2 problems with car?

 

Sounds like boost cut. Are you reflashed to correct this? The colder weather will do it; once you go over 20psi, you'll cut. Reduce boost to ~19psi and the problem will go away.

 

I was thinking the boost controller might be set to high. And yes, it was a cold night that it happened.

Any ideas on why my EVO is shaking and rumbling?

 

Something seems out of balance.

Wheel?
Clutch flywheel?
Drive shaft?

 

bump

 

friend i dont know what you have installed on car.
check your tyre lugs first.
Recheck your clutch for broken springs
Check Boost, usually evos overboost after 1.3 bar(limitations to save engine)
check your wastegate.
Agree that sth is out of balance