[Zerosoul]

first of all, I have HKS EZ, and a slightly slipping clutch. BPU at 18psi.

while having some fun with my friends on HWY I suddenly realize 25psi on boost gauge! I was sacred so I let off the gas and turned down the EZ control knob all the way to 12'0clock position (which usually gives about 14-15psi) and got 18psi.
however, this only lasted for short while and everything went back to normal.
It happened tonight again though...I made several pulls without touching the EZ setting at all, running 18psi consistantly and suddenly on 1 pull I get 25psi again!
I checked all hoses and everything seems fine..(especially double checked the hoses going into wastegate actuator from EZ step-motor).

anyone has any idea why I get this sudden raise of boost? would slipping clutch have effected my boost level?
this is not just a quick spike of boost, it stays in 25 psi for as long as I'm on the gas and holds steadily.....WTF!?

any help is appreciated.

thanx

Jonas

 

[Grandnat]

Maybe it is because of your slipping clutch.

 

[Grandnat]

I have already given you a perfectly valid solution.

and hell yes I am being funny! I thought it was hilarious!!!!!


ok your problem:

think about how it works man. the wastgate works by spring pressure. if the spring pressure it 10 pounds, then it takes 10 Psi of boost to overcome the pressure and open the puck.

no matter how much it cost or how damn sophisticated your boost control device is, they all work the same. just a glorified bleeder valve.

so if you want to run 18psi. and you have a 10psi spring you need to bleed off 8psi of boost.


you are seeing alot more boost than you should.


think about it like it was just something simple not some crazy voodoo black magic.
it is simple, so take logical deductive steps to solve your problem


first of all take the damn boost controller out of the loop. go back to stock...see what happens.

if that doesnt work go closed loop, which means just run the boost hose from the turbo to the waste gate.....in other words take all the boost control (stock or other wise) out of the equation.

you will most likey find that somewhere along the line you have solved your problem. If not then the problem is most likely a cracked or spilt vaccum hose.

or if you are afraid to get dirty ...write a goddamn check and stop asking people...

don't ask me why I helpped you after you were such an asshole.

I do expect a thank you

 

[Silver Orchid SP60]

Check your VSV's and actuator hoses. If the EVC is hooked up like the DSBC check the vacuum caps. I did have an over boost problem on the stock twins when the cap on the brass actuator close to the bottom VSV used to pop off. Check that.

 

[Zerosoul]

will do...again.
thanx!

 

[Grandnat]

Like silver orchid said.... (and me) something somewhere is bleeding off air. that air is not being seen by the actuator.....there inlies the problem.

 

[Zerosoul]

Grandnat...

as I mentioned....I HAVE checked all my hoses and caps and they are fine. but I am gonna double check it again.

I am not some idiot who knows nothing about my own car. I have studied intensively on how the sequential system work and yes, I do know how all actuators, VSV..etc works.

however, there are always special cases.
for example, wastegate not reacting right...or say sudden change of temperature.
I am using HKS EZ, basically a manual boost controler. the reason why I am asking if there is a possible relation between my slipping clutch and over boost is because I have been running consistant boost for more than a year now, havent touch that knob for a long time...

thanx for your input anyway, remember, no one likes a smart ass.

 

[Silver Orchid SP60]

Make sure u check here on #3

Not just that it's capped but that is firm. I had to cable tie this one because it popped off at high boost.

 

[Zerosoul]

awsome, thanx for taking that picture...I will make sure that cap is on tightly.

 

[Grandnat]

Grandnat...

as I mentioned....I HAVE checked all my hoses and caps and they are fine. but I am gonna double check it again.

I am not some idiot who knows nothing about my own car. I have studied intensively on how the sequential system work and yes, I do know how all actuators, VSV..etc works.

however, there are always special cases.
for example, wastegate not reacting right...or say sudden change of temperature.
I am using HKS EZ, basically a manual boost controler. the reason why I am asking if there is a possible relation between my slipping clutch and over boost is because I have been running consistant boost for more than a year now, havent touch that knob for a long time...

thanx for your input anyway, remember, no one likes a smart ass.

Thats why I said run it in closed loop mode.....completely bypass the boost controller...that will tell you if it is the actual wastgate actuator or even a sticking puck. if it holds steady that way then you know you need to work backwards and see when it reappears.
I do not have intamate knowledge of the supras waste gate system but theorhetically all waste gates work the same. if you run it directly like I suggest than you will only get the same amount of boost as the actuator spring pressure is rated at.

if it is 10lbs then you will get 10psi max....but the point is to determine if it is holding steady. so youa re going to need to determine the spring prssure these cars come with stock.


it is possible that a VSV is sticking open....this will also bleed off more air. it is just s stepper motor....sometimes they can get dirty and stick open or not seal properly.


there are alot of possibilites....but you need to get to the most basic point and deductively figure it out.

 

[Grandnat]

bottom line is you are probably loosing air somewhere along the line.....you need to find it.

 

[Zerosoul]

I am leaning more towards my stepmotor now. when I turn off boost controler (hoses still hooked up), I run 13psi steadily in all gears. which means I am not bleeding the air going into the wastegate.

I am gonna put back the little filter that comes with HKS EZ so that no more dirt can get into the stepmotor...though it might be a little late.
thing is this only happens once every 10 pulls...=not very often, but enough to worry me.

as long as its nothign to do with my slipping clutch, then I can sleep well tonight...

Grandnat, I deleted my earlier post. thanx for your help also. but I really dont think your first post is appropriate either.
BTW, yes I do work on my own car most of the time. been working on it for over a year now, did all installation and fixing problems, its just I have not delt with clutch related problems thats why I post and ask for advices.



Jonas

 

[NOVAsupra]

what the hell, was the original post deleted or something? or am i just going crazy?

anyway, like i said in the earlier post, it's not your clutch, i don't seen any possible way it could be your clutch so stop referring to it. if you wanna drop 1k and get an excuse to buy a new clutch then so be it but it isn't going to fix your problem. check all your hoses, maybe even replace all your hoses and put zip ties on all of them.

btw, 13psi with the bc off is high, i can only manage around 11psi at *most* stock, i had the bleeder t and only got around 14 during the summer. Of course this is all relative, every car is different but from my experience this is high and as you increase your boost pressures the vaccuum leaks get more obvious.

 

[Zerosoul]

13 psi should be normal with intake, DP, exhaust, FMIC, with BC turned off.

I am not making excuse to buy clutch...it is slipping. so I know it has nothing to do with the clutch now, just making sure.

as I said, the car is not bleeding air...otherwise I would of gotten much higher boost even with BC turned off. could be stepmotor but I will double check wastegate hoses again...and again.
to come to worst..my wastegate just gave up or something...then single right?

 

[NOVAsupra]

you could have a hair line crack that doesn't show up under low boost but really opens up at high boost. i'd check your intercooler hoses, that's my advice, it's up to you if you listen or not. better yet, pressurize your intake tract, i guarantee you have leaks all over the place.

usually if your stepper motor goes bad it won't relieve the pressure so you'll run low boost, just fyi.

 

[Grant]

Its doubtfull the wastegate is broken. Ahh the merits of ball-n-spring MBCs....