try switching the EGR solenoid vacuum lines.
If that doesn't work then block off your EGR and see if that does it.
I used a beer can, I cut out a diamond shape punched 2 holes in it and placed it between the egr and the intake.

 

cleaned my EGR nicely and that did not solve the problem.

checking my PCV next.

 

My boyfriends BT GLI sounded the same way. One of his vaccum hoses to the manifold was dry rotted. Did you check all your hoses

 

checked the PCV and nothing either. After installing a new one, i let the car idle until warm and it seemed to be fine. idle at the normal RPM and no spuddering or anything. took it for a quick spin around the block and still ok. then finally took it for a 10 minute ride and there it is.....back to spuddering.

 

Common issue. Check your spark plugs by the way? My evo VIII is doing this too and we're sitting here scratching out heads... Egr? Fuel Pump Regulator? Battery? Sparks? I have an Espilar Turbo-back exhaust 3in-4.5in, and even at 900rpms mine still sounds like yours. For mine it was misfiring, so I replaced the sparks. All's good now but when my car is stopped on a slant it starts to sound like that....this just happened about 2 hours ago when I came home from work. Gonna post my issue up here...as soon as I find the "post" button lmao

 

My 8 does this also, but I have cams. Mine will go so rich the AEM wideband will blank out then it will go lean and blank out then go around stoich and back and forth then idle fine, then drop to about 400-500 rpm's and stumble. This is a real PITA. I am already hating driving the car in town and have only owned it for 2 mths. I have tried tons of things and no fix, but I will have to check the EGR tomorrow. I have to drain the gas in it anyways, the Warden drove it tonight and put 87 octane in it.

 

the Warden

 

As i said earlier to check the egr... karma came and kicked me in the butt.... My egr **** the bed and last I tried they were all on back order. Going to call one place in the morning (here in NY) and see if it's available. Been following this closely so keep posting so my brain cells dont get too over worked looking at the engine thinking "wtf now?!"

 

and this person is still breathing how? just kidding... although i would of flipped out something lethal.

 

where is that my evo 4 is doing this really ****y idle thing

 

anybody have any luck?

 

my buddy has an 8 with stock cam's and his car ideals like this.....tuners can make a car lop more or less so it might be in your tune...?

 

So it's been about 1 month after I cleaned my EGR and I haven't had the problem since. I've fixed the problem!

 

Sorry to hijack this thread, but I'm having the crazy loping idle issue on my '04 Evo 8. I'll post up a video clip soon.

I have some head work, HKS 264/264 setup, and some bolt-ons. I recently stalled twice because the idle dropped so low after warming up around a week ago (before I knew the idle was starting to become lopey).

About a month ago, I did remove some of the hoses to the intercooler, swapped my 8 turbo for a newer, much cleaner 8 turbo. I was thinking that maybe a boost leak would cause the idle issue.

I also thought maybe it might be due to a misfire. I bought the car at 107k miles in March 2010 and it is currently at 116k. So, I really should change out the spark plugs to see if that might solve the issue I have.

I'll contribute to this thread to dig up some answers.

Good luck with you all.

 

I failed to mention that this idle issue began a few days ago. Here is a video clip:

http://youtu.be/Y7a0Kf7hOu8