EVO VIII boost problems

[koho2731]

I've been trying to help my buddy out with his EVO, becuase the dealership couldn't figure out what is wrong. The problem was that he couldn't boost above 6 psi. I swaped out the stock WG act for a forged adjustable one, becuase he had already bought it and the stock one was dented. Now he is boosting to 11.9 psi. I adjusted the atcuator arm as far closed as I could. I also retorqued the IC pipes and exhaust bolts. I also cked the turbo for shaft play and there is no in and out play. I'm starting to run out of ideas I still need to do a boost lk ck and guess do a compression ck. The problems started after his car was stolen and the jacked his EBC and Turbo timer.
He replaced the EBC with th Eo1 which he had before. The only mods he has done is the EBC, old adjustable HKS SSQV and exhuast both were all ready in the car when he bought it. I realy haven't delt with internally gated WG to much before or adjustble BOV's. I tightend his BOV a little bit also tonight but it didn't do anything. Any ideas? BTW EVO's are much more of PITA to work on then DSM's

[SilverTurboRidin]

Your absolutely positive the BOV isnt leaking under pressure?

[koho2731]

Not sure I still need to do a boost lk ck. I don't hear any thing but he has it mounted damn under in the front bumper, but I would think not since it wasn't lking before the car was stolen.

[95nracer]

Doesn't the EVO come stock with the Twin Scroll? Is there a vac line that goes to it?

I doubt its the BOV, buts its a good idea to do a leak down test.

Replaced all of the vac hoses to the boost control solenoid and control unit? If the control unit still has the little filter on it maybe remove it and try a couple of runs.

[koho2731]

It's a twin scroll, but I haven't seen any vac lines off the turbo itself . I don't think he replaced the vac lines to the controller or the solenoied. I'm thinking it has to be a boost lk problem because he isn't even hitting spring pressure. The onther thing I guess it could be it the E01 boost gauge is off.

[peteyturbo]

Check the boost controller 5 more times..If boost was leaking somewhere you will still make more then 10psi unless it like a "wooley mammoth" type leak..Very doubtfull its the BOV..I say boost controller setup, and you HAVE to make sure the Forge WGA is adjusted correctly..Plus, are you using a boost gauge?? From what scource? Or is it just the EBC boost display??

[koho2731]

Check the boost controller 5 more times..If boost was leaking somewhere you will still make more then 10psi unless it like a "wooley mammoth" type leak..Very doubtfull its the BOV..I say boost controller setup, and you HAVE to make sure the Forge WGA is adjusted correctly..Plus, are you using a boost gauge?? From what scource? Or is it just the EBC boost display??
I don't mean to sound ignorent or anything, but how do you properly adjust an adjustable WG? I've haven't dealt with them before I have it as tight as I could get it and still hook it up to the flapper. He just has the EBC display for the boost gauge. When they stole his car they just took the display/control unit. I'll have to double ck the source he is using. He is bring me the malule tonight so I can read on how to use the E01.

[koho2731]

I forgot to add I logged a run in his car with my logger and he had a load of 17 at idle and 5* of timming. I'll make another log to ck air flow and see what the Map is doing too.

[silver05bullet]

does he still have the boost controller installed or after it got stolen did they just put the lines back to the stock solenoid, if he didnt replace it and the dealership just connected the old lines that where ran to the ebc, then he needs to replace the line going to the turbo because in a stock evo it has a pill in the line that allows the stock solenoid to control the boost

[silver05bullet]

nevermind since you guys put a new boost controller on, recheck that you installed the lines correctly or just run new vacuum lines to the boost controller to make sure thats what it is.

[silver05bullet]

If this doesnt work do this if he has a stock catalytic converter on the car, take the cat off (4 bolts) and do a pull with the car with the cat off it he should boost, in many cases the evo's stock cat gets clogged if you beat on the car. If that doesnt work let me know on here

[koho2731]

He has an after market cat on the car, but I bolt up his "test pipe" and se if that helps

[SexyDSM95]

Go do the boost leak test then come back and let us know the outcome. Do the basics first before you go off on a tangent getting yourself mixed into more theories/trouble then the problem at hand.

[koho2731]

It would have to be a massive boost lk for it not to boost higher but I will not get to mess with the car until friday again.

[SexyDSM95]

It would have to be a massive boost lk for it not to boost higher but I will not get to mess with the car until friday again.Well the boost leak test will also determine if you have any un-metered air that is getting sucked in also.

[03tarmacblack]

checks for leaks like everyone else said, esp. intercooler pipes. Is he running the stock intake ? Search evoM im sure someone has had the same type of problem.

[peteyturbo]

You would definitely hear the leak "loud" if 10psi is maximum boost..Check the pinswitches on the EBC..Also make sure your Forge WGA is not causing the flapper to hang open slightly when it should be completely closed, this would also cause the problem you are describing..

[peteyturbo]

"leak down" and "boost leak" are two totally different tests..I think you mean pressure test right??Doesn't the EVO come stock with the Twin Scroll? Is there a vac line that goes to it?

I doubt its the BOV, buts its a good idea to do a leak down test.

Replaced all of the vac hoses to the boost control solenoid and control unit? If the control unit still has the little filter on it maybe remove it and try a couple of runs.

[peteyturbo]

Not trying to "school" you or anything but it would actually cause "metered" air to ecape causing an overly rich AF condition and loss of manifold pressure..If you had a leak in your air intake after the MAS and before the whistler, it would cause the scenario you described..:mrgreen: Well the boost leak test will also determine if you have any un-metered air that is getting sucked in also.

[peteyturbo]

You want it adjusted so the is tightness to the flapper hinge..A good way to start is this..
Unhook your EBC..Tighten (shorten) the WGA rod until you get about 15 psi of boost just on spring pessure alone..Then install your EBC and work from there..That should set up your WGA nicely..What spring are you using??I don't mean to sound ignorent or anything, but how do you properly adjust an adjustable WG? I've haven't dealt with them before I have it as tight as I could get it and still hook it up to the flapper. He just has the EBC display for the boost gauge. When they stole his car they just took the display/control unit. I'll have to double ck the source he is using. He is bring me the malule tonight so I can read on how to use the E01.

[95nracer]

"leak down" and "boost leak" are two totally different tests..I think you mean pressure test right??


Yes, sorry thats what I meant.

[olsookie]

never found out what was wrong yet? i'm just curious.

[koho2731]

never found out what was wrong yet? i'm just curious.
Not yet I probuly will not get to work on the car until friday night. We work oposing shifts so it's kinda hard to get time to just work on it.

[koho2731]

Okay here is the update on his car. I'm not going to try to fix it any more, because he found out that the car has major structural damage. He is going to try to get the dealership that he bought the car from to buy it back. I don't know how that is going to work out for him, but he wants to get another Evo(used). BTW he did do a boost lk ck and it was good.