Weirdest noise in boost
Weirdest noise in boost
ever since i got my 05' evo its made this random sound. there are only two things i can accurately describe about it: it only happens above 15 psi or so and it is inconsistent i have a greddy profec e-01 set to 20 psi. When i do pulls it happens at random but only above 15 psi or so. its almost like the rice crispys sound you hear on an open dump but with the added sound of "i think something tells me this isnt right and its a matter of time till it breaks". id call it a turbo death noise. Other than my tephra modded ecu and the profec bc everything else is stock besides the forge dv i just added. Since the wastegate opens on every pull it cant be that...or can it? im running stock exhaust unlike my buddy with his open dump and therefore it dosent quite sound like a typical wastegate opening up. thanks in advance.
a buddy of mine had a similar sound around 18psi. no power loss or boost leak. it turned out to be his greddy type s bov. the rubber diaphragm had a little rip. swapped back to stock 9 bov and noise is gone. have you checked for shaft play?
it definately isnt the bov because it happened b4 the new one was installed plus the new1 added alot of beneficial effects. i noticed one thing tho to pinpoint this: it only happens when my afrs get a little leaner... at the same pressure...my afrs will go to 11.1 to 11.6 in full boost at any rpm and the noise is consistant with this. at random, the afrs will switch back to 10.0 to 10.2 with a noticeable increase in power and the noise disappears and the engine sounds normal. is this a stuck injector? a bad injector seal? a boost leak? a tuning/ map switiching issue (tephra mod is the rom im using)? a fuel pump issue? or a turbo issue? what in the world would do that without changing manifold pressure? or if it does change the manifold pressure its minimal and im not noticing it... on another note is that noise the turbo responding to the heat from higher afrs?
I am almost 100% sure that the reason the "rice kirspy" or similar valve ticking noise sound is happening is because the way the Greddy Profec B's solenoid is mounted directly onto the metal of the car. I had this happen on my Evo IX when i was running the Greddy Profec B and did the below to fix it in no time.
Put a rubber grommet between the Greddy Profec B Solenoid and the metal of the car to totally do away with the sound. Must be rubber.
I am also assuming this is what happens with the Grimmspeed EBCS. I am buying one next week and will place a rubber piece between it and the car.
Hope this helps and sorry to revive a old thread but it is a common question and a ***** to solve.
Put a rubber grommet between the Greddy Profec B Solenoid and the metal of the car to totally do away with the sound. Must be rubber.
I am also assuming this is what happens with the Grimmspeed EBCS. I am buying one next week and will place a rubber piece between it and the car.
Hope this helps and sorry to revive a old thread but it is a common question and a ***** to solve.
Last edited by MetalSpoolDoom; Jul 10, 2010 at 03:02 PM.
