The original owner messed with my toherwise stock 03, messing up the boost, and sold it. I already shot down one problem, and am hunting another. I think the thing might have had some sort of boost controler on it. There's a hole cut in the back of the sunglasses cubyhole under the HVAC controlls. He messed with the vacuum lines for the bov and wg. The dealer fixed that.

There are supposed to be those brass "pills" in some of those lines, can those be detected by squeezing the appropriate hose? The car runs only to about 14-15 psi max, kinda like what I would expect to be in the boost retard at higher rpms. I'm wondering if one or both those pills could be missing.

At the dealer it looked like some of the vacuum hoses had been replaced, they had to add the T connector back in. Does the hose legnth factor in to the proper working of the pills?

 

Easiest fix is to buy a hose set and install it. It has the restrictors in the right locations.
See the sticky thread in Evo General if you want the part number, it is on the last page.

The is one about an inch away from the boost soleniod that you can squeeze the hose to feel. The other one is by the turbo nipple and you won't feel it probably because the hose is so short. I'd be willing to be you are missing the turbo pill, if not both.

 

I don't suppose the hoses (MN143555) come with some sort of instructions as to what goes where; is it just a length of vacuum hose and the brass pills? I might wind up having the dealer do it.

It looked like the original vacuum hoses had been totally replaced, sans the T fitting. I also need to come up with the time to mess with it. I'd still love to know what the frak the OO thought he was doing to it.

 

There is another member on here that is missing the same part. I think the dealer told him it was on national backorder.

 

It's easy to install. Get it and I will tell you where is goes.
It's an assembled set so you just plug them in. Pills are already in place.

 

I bounced my situation off another Evo driver. He thought that I need to check my vacuum lines again (the dealer set mine up), that the wastegate is not getting assistance from boost pressure. I'm getting a max of about 14psi, and he said that is what the WG spring can do by itself. He said that the pills prevent higher boost only, and that missing pills would create an overboost situation.

 

Your friend is wrong. Boost does not assist the WG actuator.
boost pressure from the compressor side is what opens the wastegate. There is a restrictor for the amount of pressure that can enter the lines from the compressor housing. The boost solenoid bleeds pressure ffrom the system to keep the WG closed. You remove the solenoid restrictor and too much pressure is bled from the system and the WG stays closed (overboost). You remove the restrictor at the compressor housing and you get too much pressure in the hoses and the boost solenoid can't bleed it off so the WG opens under boost pressure. The boost control is a bleed system. The wastegate is a pressure differential design. The spring is not a 12 lb spring. remove the WG hose altogether you will get a lot more then 12 psi of boost.

Get the hoses, they are $14 on MitsubishiParts.net.
At the Tee the Red hose goes to the WG actuator, the shorty black with the restrictor goes to the compressor housing and the long one goes to the boost control solenoid.

Also, you don't want the top restrictor in and the compressor housing one out. That can damage the WG actuator diaphram because it can't handle full boost pressure.

 

Thanks for all the help. My hoses are on order, and should ship soon. I'm hoping this cures what is bugging my Evo.

I still need to find time to pull out my airbox and look check the existing hoses that are there now. The hoses are generally too long and loose. There is no "red" hose. I'm wondering if there are no pills in it at all. Finding time to look at it when it is light and the engine isn't hot is a problem this week-weekend.

What does a healthy Evo turbo sound like? I hear the whistle of the turbo and hear sort of a BOV type noise at the same time. I have to push it somewhat to get 14psi. the dealer said my BOV (stock) was good, I don't know what you can tell by looking at it.

I drove another evo months before this one came along, I don't remember it making those noises. I'm also concerned about WG actuator diaphram damage.

 

All hoses are color marked on the Evo. Usually with small length wise strips. The red I am talking about is at the end of the one hose all the way around. You can't miss it.
You are probably hearing it more because the wastegate is opening up considerably, if not all the way. This is changing the whole turbine wheel flow characteristics.
I'd be willing to bet you are missing both restrictors and none of the hoses are original.

 

just buy a mbc and turn it up to 21. Throw some iradium plugs in and your good to go.

 

There is a white sticker under your hood, on the driver side. It has the correct locations for the stock hoses, one restrictor pill should be 1-2" from the boost solenoid l closest to the harness, under the air box, in the line going back to the WG and Compressor. The other restrictor pill is 1-2" from the compressor housing, in the shortest hose of them all, from the compressor housing to the "T" fitting. The hose from the black intake pipe wil go directly to the farthest side or the boost solenoid, no "T"s or other connections. You should be able to squeeze the hose to feel for the restrictors.
Good Luck

 

I wound up at home today, so I pulled my air box and looked at the hoses as they have been since the dealer did onto them. No color codes, and by touch, probably no restrictor pills at all. This should be a slightly hacked photo of what I have now, made of 3 photos. The dealer's zip ties on the replacement T connector can be seen:

Will the replacement hoses need zip ties? I checked the hoses against the diagram, the placement looks correct.

 

Why is that T connector there? That doesn't look right.

 

Yeah that doesn't belong there. Don't know what they thought they were doing.

 

The diagram under the hood shows a T connector, doesn't it?