Okay guys help me out. 95WRX Magnex Exhaust, KN Cone Filter, Superchip Fuel Cut Remover/Bleed Valve. My car has an intermitent boost problem. The boost is normally 15psi but sometime will not go any higher than 8psi. Sometime it is fine all day tehn will drop to 8psi for a day or a few days or just every now and then. It is as if the ECU is going into safety mode. When it does the turbos just doesnt want to spool up it just sits at 8psi. Really annoying as it usually happens just as i get a SAXO up my ****!! Any help appreciated.

 

Im not too sure u could possibly have a minute pressure leak where ur bleed valve is which can trigger the safery on the ECU which will then not let the car exceed a set boost. Bleed valves are not the safest things to use when playing around with boost as they always flucuate...

 

B.T.B.

Now mate.

I had a problem with my Leg T where i couldnt get over 8 psi.

It turned out to be a sticking wastgate rod on the actuator or something related to this.

I took the heatshield off and moved the rod back and forth and it clunked.

I put everything back on the car (pipes etc that I working my way through) and went out for a run ......

Shazam.... Boost back to 15 psi.

I was advised that you can test to see if your wastegate actuator thingy is fooked by taking the pipe work off from the boost nipples on the tubo and actuator. I put a roofing bolt up each pipe just incase.
I went out and VERY VERY CAREFULLY, thats VERY VERY CAREFULLY!!!!! tried the boost out on the car myne was ok and felt it boost up beyond the 8psi it was sticking at.

I fyours wont go over the 8psi mark then it could be that you have a week actuator and its bleeding the boost off at this ammount.

Hope this helps if not its one less thing to try in the elimination process.

All the best

Ste.

PS

If I'm mis-advising this guy, someone please flame me and stop him from doing summat he should be doingwith his beloved.

I did do the above though without death, seriouse injury or dammage to property or vehicles:

soz about any poor spelling i'm possed outa me ed

 

ecu is in limp home mode.. check the superchip is actually removing fuel cut..

try dropping the boost a little bit...

David

 

Cheers guys i will have a fettle tomorrow and see what i can find. I figure the fuel cut must be okay cause it will run at 15psi without problems for upto a day sometimes. I will also check/clean the boost solenoid to see if that helps too. I hate intermitent problems.

 

I tried dropping the boost to 12psi (13psi at peak) and went for a run earlier today after reseting the ecu. It was okay for a while then dropped to 8psi again for an hour or so then came back to 12psi later!! I feel like the car is taking the pi$$ out of me!

 

What fuel do you use?,

Sounds like the ecu is detecting knock/detonation which will make the ecu go in to limp mode and reduce the boost to around 8psi.

 

Try looking to see if the ECU is detecting/registering a fault and therefore going into 'limp home mode' CLICKY

Cheers

 

mine did the same
the wierd thing was i was running a dawse device
i removed it cleaned it, gave boost control back to the soleniod, still no joy

refitted the dawse after another inspection, no joy
tried lowering the boost as much as i could with the dawse, no joy

got seriously pissed off and wound te dawse right the way in and nearly snapped my hands on the steering wheel
i was really pissed of and give it a bootfull from a layby and shat my pants, its been fine ever scince

 

Okay guy i took the heatshield off the turbo and checked the actuator arm was moving freely and it was. I also cleaned the boost solenoid out with brake cleaner and WD40. I then also noticed the bottom pipe on the solenoid (3 way solenoid) was hanging off!! This pipe connects onto the black box between the MAF Sensor and the turbo. I put it all back together and made sure the bleed valve was fully closed. I went for a run and everything is okay making a steady 13-14.5psi. So fingers crossed. I will be junking the bleede valve and Superchips fuel cut defencer. I am gfoing to get hold of a ScoobyECU chip for the ECU.
I always run Optimax or Super if i have to.

 

i wish i hadnt posted my above thread as mine has done it again (3rd time now in 12000 miles)

boosting to 0.7bar max

took of the dawse, checked inside, ball is free, blew down the rubber pipes to make sure there wasnt a blockage, all is well, stuck it back together and still no joy

i suspect the wastegate can sumtimes "jam" up? or sumthing?

 

You prolly need to reset ECU

 

how does the ecu control the boost levels if the boost soleniod isnt connected up? (its plugged in but the dawse device is controling the boost levels)

this has always confused me?

 

as epected a ecu reset did nothing at all (never expected it to)

intercooler is coming off tomorow and all intake pipes to look for blockages

 

Perhaps the actuator/wastegate poppet has jammed in the open position thus only allowing minimal boost. You could try checking the operation of this by connecting to a 'foot pump' and observing the stroke.

 

tried all of them

even adjusted the wastegate/actuator arm thing
max boost in 5th gear with the dawse device just about totaly wound in is 0.9bar

taking the IC of tomorow
small chance that one of my old turbo blades has reapeared and sumhow blocked up the small metal pipe that comes from the turbo to the dawse device (strange)

i was going to try a foot pump but couldnt find a suitable adapter to hook the hose up

after this im going to have to look for split "boost" pipes (turbo doesnt sound like its boosting hard and the boost is being leaked away) turbo whine sounds "slow" so i dont think its that

 

i tried this as well, although i didnt put a bolt in the pipes i just disconnected them, went for a run, boost was still the same

how does the actuator work?
is it a piston or os it a diaphram (easy to split)

 

The actuator from what I remember has a diaphragm and a spring return (Pressure pushes rod to open WG poppet and spring returns it) Try testing with a 'Foot pump' or something similar to test the stroke action. If the diaphragm was split you would get overboost, if the spring is damaged/broken you may get the symptoms you are describing.

Cheers

 

i still havnet tried the foot pump idea becuase ive been busy getitng drunk

but i did do sum small tests on the actuator

i removed it from the wastegate and pulled it out as far as i could, then i released it and it slid back in

i added a rubber hose and pulled it right out, then clamped the hose and let go of the actuator, it came ina tiny bit then stopped, when the clamped rubber hose was released it went in fully

i have a feeling that its not the actuator, although i plan to do sum more tests tomorow

 

Have you tried stretching the spring a little bit in the dawes , this should increase the boost presure , over time you may have squashed the spring slightly

Mark

 

thats possible
but how it can go from 1.3 bar down one road fine, then slow down and get behind sum traffic for a few miles, then trying the power again and finding it had dropped it 0.7/8 bar is baffleing

the spring could be compressed and such, but i would expect that to happen gradualy if at all

not suddenly, i have not looked at the car today/yesterday as i was on a 12 hour clubbing bender and i feel a touch "mashed"

i have a idea in my head, when the turbo blew up and the blades went all "broke" i struggled to find the parts that came of the turbo blades, i found a few tiny little specs in the intake pipe, but couldnt find anything else

im wondering if sumhow one of them got stuck in that small pipe from the turbo to the dawse device restricting flow??

feasible

might try the actuator from my ihi vf and see if that works at all

 

yay i fixed it

took the intercooler off, and checked the hoses
tightend a few up, no joy
wound the dawse right the way in
no joy, but i could hear the turbo spool up really fast but the boost wasnt deliverd, i could also hear "air"
now i could here a whoosh with the old ihi22 turbo but with the td04 fitted all i could here was a whine, i i thought "air leak for defo"

removed the TAS piston recirc dumpvalve and had a look

saw the piston, prodded it and it was stuck, shoved it with a screw driver and it moved a bit and was still stuck, i blocked off all of the dump valve pipes and went for a drive while sum oil worked its way into the dump valve

holy ****
forgot that the dawse was right in 100%
stopped amidst sum crazy chattering noises
wound the dawse out a few turns and did another run @ 1.2 bar

sorted

my question is
can a td04 be ran without a dump valve?
i know the td05 can and i know the ihi vf22 cant

yay or nay?