When I let off the gas while cruising , or release the throttle to coast, I get a very brief (~1 sec) whistle. It's hard to hear, but I can make it out. Is it normal and coming from the S-DAIS, or should I have it looked at?

Thanks.

 

It might be your blow off valve

 

the engine makes weird sounds like that. I like speeding up so I can let off the gas and hear the "turbine" spin down.

 

I get that whistle too... although mine has developed so that somtimes it will be continuous at certain RPM's and powers... I never used to get it...

Anyone identify what it is??

 

yes, it's valves opening in the motor. It's been talked to death in other posts...

 

I have the K&N drop in filter.

 

Unfortunately no, it isn't my blowoff valve. I wish it was though.

 

This sound is as loud as the motor and can be continuous at certain RPM's... it's surely not the ports opening... what other valves are there.. and why did they not whistle for the first 10000 miles??

My engine is 100% stock... no K%N filters or anything.

 

i get it too, makes me think the 12 are chasing me again!!!

 

Same here... stock as they come... I actually really like it.
Gosh, epitrochoid, everytime I see your avatar I crack up... it never fails to amuse me.

 

its from the jdm mazda site...to me, its looks like some guy is maving love to the keyhole, anyone know what the japanese says?

 

i just assumed it was the rotor winding down...

 

lol. My first post agrees with you, Mike, but my second post disagrees with both of us because I mistook this thread for another one.

With an aftermarket catback, it's fun to rev up high in 1st gear, then let it spin down.