mike 99gsx

Have you done a compression test? Just wondering if you have an exhaust valve issue? If the test is normal, you probably need to inspect the turbine wheel.

PVD04

iTrader: (23)

People need to quit posting the stock boost levels for the Evo. They do not in any way apply to this problem. If there is not a boost signal to the WGA the ECU has no way to control boost. Therefore, the stock boost levels can not be maintained.

-Paul

Tommyfacekicker

I know this is as old as my car but did you guys ever find the problem? Any feed back would be greatly appreciated. Thanks.

94AWDcoupe

iTrader: (125)

Yes. had to think a bit. didnt even remember making this thread. there was a problem with intake pipe. partially blocking flow from MAF.

4G63Rules

iTrader: (10)

You remembered the problem this car had from almost 11 years ago? Holy hell. I don't even remember whose car this was.

94AWDcoupe

iTrader: (125)

I remember the color and cars owner too.

Tommyfacekicker

I really wish I could find my problem. Unfortunately I am not running a maf

94AWDcoupe

iTrader: (125)

can still happen with speed density.
try running with out the intake. turbo only

drive955i

iTrader: (6)

Plugged catalytic converter? Could restrict exhaust flow enough to generate back pressure, resulting in less turbo spool (zombie post resurrection!).

Tommyfacekicker

I'm running no intake on my turbo. I have straight pipe no cat. I think my turbo wasn't mated correctly to the exhaust mani. I took off my exhaust mani, now just waiting for a new one n hope it was just my exhaust mani giving me problems.

Tommyfacekicker

Ill keep u guys posted on the results

cerevo

iTrader: (1)

You get it sorted? I've chased down my few small boost leaks but ever since my new engine and hta71 I cannot get the thing to build more than 13 to 15 psi.

What sucks is my Evo 4 turbo on all the same equipment (hoses, clamps, boost leaks) could hit 20 no problem. Starting to think my turbo is broken.

Tommyfacekicker

I think I fixed my problems, my exhaust mani was leaking from where it mates to the head so I got a new stock ported exhaust mani and made sure it lined up n now there's no leaks there(used sea foam n saw no more smoke from there). Then my throttle body had leaks so I picked up the fb 70mm n haven't done a boost leak but so far the car runs great. Changed my plugs n stock coil boots n checked compression n it was all good. Got the car re mapped and afr's look good, car feels great, but boost gauge doesn't show anything past 22 psi, sometimes it'll hit 24 psi. Maybe my gauge is reading low now. Turbo has no shft play, no oil leak(it's also a new turbo), but he stock turbo was also able to hit 26-27 psi (at least that's what my boost gauge showed). So I'm gonna save up n buy another gauge n see what it really says.

Tommyfacekicker

I also took off my intake mani and reinstalled it bec I think my install was crappy the first time or maybe it had something that was possibly leaking from the intake mani to the head. I'll update after my next compression test.

cerevo

iTrader: (1)

That the same issue I'm having, stock turbo would hit higher than this turbo. I've boost leak tested probably 10 times trying to find the leak, but there can't possibly be a leak big enough to cause it to not gain more than it is.

I think I'm going to wire my waste gate closed and see if that gets the pressure up at all and if it does maybe it's my boost solenoid. If not I guess I'll Seafoam it and see where it comes out. Thanks for the advice!