Check for exhaust leaks before the turbo I.e. cracked manifold, blown gaskets between manifold and turbo or manifold and head. Do a boost leak test and you should find your problem. Ccheck all vacuum lines for tears and make sure they are hooked up correctly.

 

Boost leak or Exhaust leak. Maybe a bad seal on the turbo header?

 

Alright guys, this is my buddy's car... I've been trying to help him fix the boost problem and I'm on the forums more then he is so I figure I'll be the middle man here. He bought the car from the dealership and they told him it was probably the wastegate actuator and they wouldn't allow us to check it over or even take the intake pipe off to check for shaft play so he decided to take a chance on it because it was being sold for way under blue book with how many miles where on the car... but what's done is done. I don't believe it is even boosting 3 lbs i believe that the boost gauge makes it seem like it's at 3 lbs but it really isn't because A) the car is slower than a Honda civic, B) i don't hear any turbo noise at all. The car runs absolutely fine as if there were no problems with it, no misfire, no stutter, or anything, it just feels slow. We have installed a manual boost controller thinking that might do something and it didn't change anything, there are no mods done to the car other than an aftermarket filter and now the MBC. We believe the previous owner had an aftermarket exhaust because we found a Perrin o2 simulator by the parking brake under the center console, also we believe the guy had some kind of data logger or engine management system because there were a bunch of blue quick connects with cut wires tapped into the ecu harness, maybe a problem there? I don't know if you can control boost levels from inside the ecu or not... and the previous owner had a turbo timer but we took that out because it wasn't working correctly anyways... We have also replaced the wastegate actuator with an brand new OEM one and still nothing, it's all connected so no it's not the flapper arm or anything like that. We have also replaced the turbo with one with 5k miles on it, figuring the turbo was probably shot and still exact same thing, and found out there was nothing wrong with the original turbo either. So now we are stuck and don't really have anything to go off of... The car has absolutely no boost but runs solid...

 

Thats messed up..check ur turbo n boost selonoid

 

Turbo is absolutely fine, it's been looked over, no shaft play, and the wheel spins freely and spins both intake and exhaust side together. We installed a MBC so wouldn't that bypass the boost solenoid? Right now, it has a MBC and the boost solenoid is still wired to the car and there is a vacuum line running from the one nipple to the other so it's routed back into itself, I did this because we saw on the a forum that you should still leave it wired in but cap it off.

 

Bad cat possibly. Cat is clogged restricting boost.

 

That would have to be one hell of a clog haha

 

to test the turbo connect the turbo nipple directly to the wastgate. this should give you 11-14 psi. if it doesn't then its either the flapper or the turbo.

 

what were the boost test results?? yea you can control boost threw the ecu but even that would build past 3psi... was the waste gate actuator arm connected to the wastegate?....

lol are you looking at the right gauge...sorry i have to ask.

 

check the timing also, sounds like it's way retarded

edit: define "slower than a civic" if the evo wasn't turbo'd, it would be similar to a civic speed-wise (probably slower... .4-.2 liters doesn't make up for 600-ish pounds

 

I know this sounds dumb and by now I am sure that you have checked and rechecked all the lines... but what is the gas mileage like? I mean we all know Evo's run through some petrol but on a car that "runs fine" not making boost is it still running through tanks of gas? If so check your LICP on both sides of the FM. I had a similar problem once and it ended up one of the elbows that comes off the intercooler was torn. I believe it was the one on the drivers side, it's connected to the pipes that run up to the throttle body. You may have to pull the bumper off to get a good look but check both those elbows and make sure the clamps are tight. A boost leak test can also tell you this. My .02.

 

Ok, we know that the exhaust manifold gasket is new, since we replaced it when we swapped turbos, all the gaskets for the turbo appear to be fine and there doesn't seem to be a leak anywhere around the turbo as we can not hear a leak nor feel one coming from there. The wastegate arm IS CONNECTED TO THE FLAPPER. And it has also been replaced. We are going to do a boost leak test ASAP and I'll report back with the findings. If it's a clogged cat wouldn't that cause a lot less exhaust to come out of the tailpipe because we can feel a lot of exhaust coming out of the tailpipe...

 

We have also checked all the intercooler piping and all the vacuum lines and they all appear to be fine, but a boost leak test will tell us for sure so we won't find out until we do a boost leak test if everything as far as piping and lines are good or not.

 

and by slower then a civic I mean my buddy lost to a Civic Si as one tried to race him and he lost. It just feels slow, I have a DSM turbo'd and mine would walk right by it as it runs right now, and I know it should be almost a dead even race considering I've raced Evo's before and that's what happened then.

 

Ok, so we did a boost leak test today. We found only one leak by the throttle body and believe it's the seals on the inside of the throttle body because the pitch of the leak changed when we opened and closed the throttle body. So were gunna replace the seals and put it back together and do another boost leak test and see if it fixes the problem.