Like the title says i need help really bad. So far its not going as planned with my evo. I just finished doing the evo 9 turbo swap with all new ICP, Invidia O2 housing, and Ex mani. So i took it to get a street tune, and could reach the targeted psi, which was 22 psi. The tuner had to turn the mbc knob almost all the way to the point where almost no thread was visible anymore. We did 3rd gear pulls and could not get past 15 psi. The evo 9 wastegate is on the preload setting so i know it has nothing to do with that. After the tune on fifth gear it almost feels like im getting fuel cut, but crazy thing is that on 3rd i dont have that issue but still cant get passed 15 psi. I switch my spark plugs and still nothing. Today earlier my car stalls on idle. It feels like it wants to stay alive but idle is verry low. So now im thinking its the fuel pump. I listen to see if i could hear the fuel pump activate but nothing. If i try to start it it will but wants to stall right away unless i keep my foot on accelerator. Will a bad fuel pump keep you from reaching certain psi?

Please give me some advice guys
Thanks

 

What was the condition of the car before, you id all this work yourself? Did you do a boost leak test, after you installed all the parts?

 

Have you done a boost leak test?

 

Thanks for the quick reply man

Well before when i had my 8 turbo it held up to 25 psi with the tune with no problem. I did encounter the same problem i mentioned about it wanting to stall, but just kept my foot on the gas and eventually just went away. Thats why im thinking about the fuel pump.
Yes i did all the work myself and checked all the couplers to make sure there would be no leak. I also used tbolt clamps to prevent cuplers from popping off. I have an HKS BOV and im also starting to suspect that it might have a leak coming from the bov.
But now it wont start without it stalling out so i blame the fuel pump for all this stuff going on

 

What do you mean you checked the couplers, as in a visual check or a actual boost leak check by pressurizing the whole turbo system. You can have boost leaks even with tbolt clamps if everything is not installed correctly.

 

Oh okay ill end up doing the boost leak test. Ive seen a thread on how to make your own test leak using things you could buy in a hardware store. Or do you recommend a shop for this?

 

http://www.vfaq.com/index-main.html

Do it yourself. It's quick and easy. I usually have my wife or a buddy sit in the car holding the throttle open and watching the boost gauge. With an air compressor, you can hit your desired pressure quickly and a leak will be obvious.

 

You can do it all yourself, if you have access to a compressor. It's not hard and way cheaper then to have a shop do it, the general rule is.. before any tune and especially after new parts are installed, you do a full boost leak test, check spark plugs, fresh oil and fresh fuel. Don't tune a car when you have issues, unless the issue is in the tune itself.

 

Thanks man for the resource. I was just reading a thread on how to make your own boost leak tester

 

I also am having the same problem as the OP. I have done a boost leak check and resolved all problems concerned with that, but I am still only hitting 15 psi of boost. Every once in a while I might get 18 to 20 psi in 3rd gear.

Could a part be bad or need to be cleaned that would cause this, like MBC, Wastegate, etc.?

 

I still haven't done a boost leak, but im thinking a weak fuel pump can cause to not reach certain boost levels, so just in case i ordered a walbro 255 fuel pump might as well do the upgrade if it is the problem.
The other part that has me thinking is a stuck open EGR Valve, but then again you would've had stalling or rough running issues. I don't know man but good luck with your problem, and please let me know if you find something as i am also having same problems with my DD

One more thing...what was the last thing you did to your car before all this happened?

 

The last thing that I did is what is weird! I was running through the gears and noticed that it was only hitting 18psi of boost. I can't recall anything directly relating to that, except going down a backroad and bottoming out on the crown of the road! It slightly bent the leading edge of my 02 dump.

Then I swapped out the clutch and flywheel and after I got done doing that I was still around the 18psi mark. So then I was out at my parents house and we were checking out the engine compartment and I noticed a pinhole leak in the vacuum line coming off of the MBC. So I pulled out my knife and cut off an inch of the hose to get rid of the pinhole and slid the hose back on and now I am 15psi. I have a Forge MBC and I can crank that thing up all day and it does nothing to the boost. So now I am wondering if the MBC is actually bad?

I'm not having any problems with stalling or the idle. When I run it through the gears it runs strong up to the 15 psi mark, but it doesn't pull like it did when it was set at 22 psi of boost, which is what the car was tuned at.

So this is why I am trying to figure out if it might be the wastegate or MBC!?! With the O2 dump on the car I was also wondering if this has anything to do with much boost is produced. If it opens to early would that keep me from hitting higher boost?

I am just trying to think of anything and everything that could cause a drop in boost pressure?

 

Wow man hopefully you can fixt it soon. I don't think the mbc is the problem because either way your suppose to get close to 20 psi. The mbc is meant to add boost and hold the boost and not taper down. Try checking the wastegate actuator. Maybe its staying stuck open and dumping all the building boost to the exhaust.

 

Update: Yesterday morning got in the car headed to work and got to an entrance ramp I like run the car down. Hit the gas and it shot up to 27psi before I could let off the gas. So all of a sudden it is working now.

I finally readjusted the MBC back down to the pressure that it was set at. So everything is working now, so something definitely seemed like it was stuck and is working properly now. I am very happy that the boost is back, that 7 psi makes a huge difference!

Thanks for the help!!!

Cheers,
JJ

 

Glad to hear that the problem is fixed. Unfortunately, I still have same problem. I'm going to do theboost leak test on Sunday so I can't wait.

I noticed one thing though that caught me off guard. My ams mbc has a liltle whole and I know its there for a purpose, but I hear a leak coming from there. Is that normal?