My Evo is still stock except for a BR air filter kit. I do have a Defi boost gauge. For a while now I've been peaking somewhere around 16-17 psi and tapering down to under 15 psi. This is according to what I can read on my gauge. So the numbers might not be exact. I built my own little boost leak tester and planned on checking for leaks last night but ran into a couple issues. The main issue was that the hose clamp on the intake where it attaches to the turbo inlet had the screw on the bottom of the hose so I could not reach it to take it off. Anyone else have this issue? The only thing I can think of is to try to get my car on a lift so I can get to the hose clamp from underneath. Seems like a pain.

Anyway, with 80K miles on my car I have expected that I would probably be leaking some from the throttle body seals. I got a pair of new seals from WORKS and when I couldn't use my leak tester, I just went ahead and replaced the seals anyway. Figured it wouldn't hurt. While I was there I checked all the ICP hose clamps and tightened them up including the clamp on the OEM wastegate. My car is an VIII so I have the plastic BOV which could possibly be a source of leaking. I will probably replace it with an OEM metal BOV from a IX.

What else can I be missing? After changing the TB seals I maybe gained 1 psi at peak. But I'm still definitely not hitting 19psi. This is a picture of my boost gauge and the orange mark is about where I'm peaking. Seems like I should be a little higher than that even stock. I thought by changing out the TB seals and tightening up all the ICP connections I'd be in pretty good shape. Any suggestions?

 

I think you hit the nail on the head with the plastic BOV...time to get a real one! (i.e. the IX like you mentioned) Beyond that, I think you do need to use your boost leak tester. See if you can get a socket on the clamp from up top. If not, jack up the car (& put on stands!), and do it from below. It could just be the BOV, or it could be one of the IC pipes, or who knows.

Good luck!

 

That's the problem, I can't even see the bolt on the hose clamp. I couldn't even reach my hand down far enough to be able to feel it, let alone get a socket or screwdriver or anything on it.

I have a buddy with a lift so I might just have to try to get at it from underneath. Thanks for the help.

 

Well you should definitely be able to get it from underneath. Nice to have a buddy with a lift as well. You could do it with a jack & stands no problem as well if you have them. Did you buy the car used? If so, I am sure the previous owner had an intake on there. Not sure why they would tighten it from below, but apparently they did.

 

That's what I don't get. I bought the car new and I'm positive that the intake tube has never been off of the turbo so it must have been installed that way from the factory from underneath. Thanks Mitsubishi for making that an easy thing to work on. I don't mind putting it on the lift but it's just a big hassle to drive 30 min to my friends for something that I should be able to simply do in my own garage.


Yeah, it definitely nice having a buddy with a lift, and basically a complete machine shop as well. All of that in has backyard garage. Here's a photo from when we were putting a locking diff in my Land Cruiser.

 

Wow...nice garage he has there! Stupid question, but the clamp did not come loose and spin down did it? I doubt it, but you never know. Very weird that if it did come from the factory that way. But you never know... One other stupid, not likely thing is that the gauge is off. Again, not likely, but if you have a spare one (or can borrow one), it couldn't hurt to check it.

The worst part about doing a boost leak test is hearing air coming out from everywhere! Being stock, you should not be leaking at your IC pipes though.

 

Nope it was tight. When I saw that the bolt was on the bottom the first thing I thought was that my boost leak was right there because the clamp had come loose and slipped down. But it was tight. I've wondered if my gauge is off, but not sure that to do about that. I also wouldn't have thought that my IC pipes would have been leaking since they've never been off ever. But stranger things have happened I suppose so I just double checked them and made sure they were tight.

So other than the possibility of the BOV, I should have taken care of most of the potential leak locations though right? Especially with the replacement of the seals?

 

If you have another gauge, you can check it during the boost leak test. Have a friend sit in your car while you test it to see how much pressure it builds. Then if you have another gauge, do the same thing and see if it reads any higher. But ya, as you mentioned, besides the BOV (which I would put $$ on that it is leaking) I can't see unmolested IC pipes leaking.

 

you will hate this problem i've seen this problem and i've done so much reasearch and trying peoples suggestions.... im 2 months in and taken it to 1 well known shop who didnt figure it out and tomarrow its going to another this time its not leaving till its fixed