I recently bought an '03 GSR with about 7k miles. When I am accelerating hard, I hear a sort of honking or chirping noise in between shifts. Is this the sign of a failed BOV (I have the stock plastic one), or is it something normal? The car feels fine, but I have never driven another EVO. I don't have a boost gauge yet, so not sure what's going on there. If it is a failed BOV, I was thinking of upgrading to the MR diverter valve. Is there an install how-to anywhere, or is it so easy that one isn't necessary? Sorry for the newb questions...

 

Do you have a aftermarket intake? I've never heard of the OEM DV doing that. I believe you are talkin about fluttering. My Forged Motorsports DV fluttered and i got rid of it. i have the MR DV and it works great.

 

I have the MR DV and it works great. The install was easy just make sure you have all the right tools.

 

I don't have an aftermarket intake, just the K&N drop-in. I think I'm just going to go ahead and get the MR valve for peace of mind.

 

Sounds like it is installed backwards. Some people do this to get it to squak and sometimes it comes from the factory installed backwards. The outlet which is opposite the vacuum nipple should be connected to the upper intercooler pipe. The outlet which is closer to the vacuum nipple should point down into the inlet pipe near the turbo. The vacuum nipple should point towards the engine/passenger side.

 

if it were installed backwards... it may make a wierd whistle noise... it'll also make it sound really ugly like the car's going to fall apart.. i had a thread about installling my bov backwards... haha

 

Got my MR diverter valve yesterday and installed it this afternoon. Thanks to hi nrg fizzle for the explanation on how it should go - according to that, my OEM one was on backwards.

As for the MR valve, all I can say is WOW. I know there have been some other threads about this, but I definitely think this is a good mod for the car. Flipping the valve around took that awful sound away, and this DV seems to be holding the boost much better. Install was a snap, like you guys said. Thanks!