Mr Chef

Help will be much appreciated:

2006 EVO MR bone stock 24,600 miles, I've owned it since new.

Ok so I noticed the engine droning - humming louder yesterday and today. It sounds like I have an intake on it but it's stock. It's louder at idle when warmed up and definitely drones with more bass from the engine when driving Especially when shifting perfectly above 6k RPM.

I didn't think I noticed loss of power but when I took it out a little it looked like the boost gauge wasn't going much higher than about 1.2 or around 17 PSI.

I jumped on here and looked around and saw alot of people suggesting to do a boost test, I didn't have the time today but I rechecked all the upper intercooler and intake piping. Made a few twists and everything is now snug, but nothing was super loose. I couldn't get to the lower clamps I'll have more time tomorrow to mess with them and do a boost test. Power doesn't seem too different. I've always hated the peak taper anyway.

BUT the sound is annoying. The stock exhaust isn't louder. It's a louder drone coming from the engine bay I just can't find where. I took it to a buddys house to get his opinion and he agrees that it sounds louder but we still coudln't pinpoint it together. I'll get back to his house tomorrow or Monday to do a boost test.

Anyone have any idea what this might be? It's not a whine, and it has nothing to to do with clutch engagement, it's throttle related. We didn't hear any whistles or notice anything at idle. And it's even loud then.

Maybe I'm just nuts.

But does anyone have any helpful ideas they care to contribute?

Thanks in advance.

Chef

Mr Chef

Other things I noticed a little more driving to dinner and back:

50% or 75% throttle out of boost to WOT of boost at like 4K produces a slight hesitation and the droning sound gets louder between 6K and redline.


At idle when warming up it is relatively quiet not quite as boomy as earlier today when totally warmed up. And not untiil I pushed boost and WOT did the droning hum occur.

I guess it could possibly be a tranny issue but I can't tell for certain.

I looked closer at the boost gauge and saw it was spiking more normally to 1.3 or so but it still felt lethargic, not as crisp as I remember.

Local temps today were in the 40's and this evening was in the mid high 20's. It used to feel stronger in the cold weather. I'm very curious to figure this out.