Hi Guys,

I know this is a bit of a common issue, but I think I've checked all the common solutions and cannot come up with anything.

Basically im having an issue with boost pressure control. At any setting on my boost controller the turbo spools nice a fast but effectively overshoots where its set to be, then settles fairly quickly after to where the controller is set. It's almost as if there is a delay in the time it takes for the boost controller to kick in and make adjustment to the wastegate.

This is an issue I've had for a while and my mechaic at the time thought it was a faulty solonoid on the boost controller. For safety i have recently been running the car with just the actuator hooked up (no vsv). The boost was nice and controlled and held strong at approx 0.7bar (10psi).

I swapped the solonoid over from my other GT-Four which has the same unit yesteday, and am having exactly the same issue. The mechanic is ex-toyota main dealer and has a fair amount of experience with the standard car. He checked all the vacuum hoses and found no leaks. So im really confused why i am having this issue.

The boost controller does have some filters "in line" and my mechanical boost gauge is T pieced off. Could these effect the controller if fitted incorreclty (wrong way round)?

The revelant other specs are below;

Hybrid turbo (TT)
Blitz induction kit on standard intake pip
HKS dump valve
3" aussie downpipe
Mongose 2.75" system cat back
GReddy B-spec II boost controller
GReddy Boost Guage


I think this is all the relevant info. Please help if you have any ideas!

_________________
1995 ST205

Have you tried turning the "gain" down on the boost controller?

_________________
JP
GT4DC Treasurer

Grey St185 RC
Silver BMW E46 M3
Multicolour yawn Honda VFR400
Silver Honda Civic Type-R

Yeah.

Right down to 10%.

_________________
1995 ST205

Hi,

is the selenoid near the turbo and actuator?

a possible reason are endless hoses

best regards

_________________
KEEP COOL UNDER PRESSURE

street legal?.....perhaps in tschibuti

Is the feed to actuator (via solenoid) coming from the normal turbo tapping or from the inlet manifold (after throttle butterfly) ?

Sounds like delay in the system, either long hoses or restriction (blocked 'in line' filter).

If your boost controller has a differential term, increasing this could compensate.

_________________
If at first you don't suck seed, try drier grain.

Thanks guys,

I believe the solonoid is tapped in where the VSV used to go i.e. to the actuator. It is located where the airbox used to sit.

The controller itself is located in the dash and I believe the feed for this comes from the inlet manifold.

I think i need to get someone to make sure it was fitted correctly. Afterall it was fitted by the people who blew up the engine fitting this and the power fc. Not really confident with their ability at all.

Does anyone here know how these should be fitted correclty? Anyone who would take a look? I can book it in with a tuner, but i dont have anyone i trust who is close for this type of "small task"?

_________________
1995 ST205

Hi,

i would do the following

prove all connectors, open them to see broken pins

prove the air connectors in the selenoid valve, one should be the in line (comming from the turbo) an one the out line (going to the actuator)

greetz

_________________
KEEP COOL UNDER PRESSURE

street legal?.....perhaps in tschibuti

Sorry,
do you have 2 ports wg actuator, and the boost controller solenoid is connected to the 2nd port ( ex Turbo VSV ) ?!?

_________________
Wolf_Tm
TM 250 enduro 2 stroke
GT-four ST205 Snowy White with selfmade 3SGTE v4.1 - [2.34kg/bhp DynoDynamics]
http://www.youtube.com/WolfTm250
http://www.facebook.com/wolf.tm

are you TSSing this weekend?

If so we'll take a gander!

I think Matt was giving the Teesside TSS round a miss?

_________________
Don
GT4DC Chairman
1994 Toyota Celica GT-Four ST205WRC JDM 269bhp @ 0.9bar
1994 Toyota Celica GT-Four Special GT 590bhp @ 1.8bar
1989 Van Diemen RF88/89 Formula Ford 1600
2008 Nissan Patrol GU 3.0L ZD30DDTi 154bhp

Yeah,

No TSS for me. Its a long drive with a slow car! Im not really sure of the actual connections, as I dont really understand which point does what.

All I know is the TVSV has been blocked and I think the controller is connected to the wastegate.

_________________
1995 ST205

Hi,

time for some pictures, and post them in here

your system should look like this



greetz

_________________
KEEP COOL UNDER PRESSURE

street legal?.....perhaps in tschibuti

Ok, but the boost controller valve HAS to be connected between compressor and actuator, and the other actuator port blocked:
check it...

_________________
Wolf_Tm
TM 250 enduro 2 stroke
GT-four ST205 Snowy White with selfmade 3SGTE v4.1 - [2.34kg/bhp DynoDynamics]
http://www.youtube.com/WolfTm250
http://www.facebook.com/wolf.tm

Oh ok, I understand.

Will go check it today!

Cheers

_________________
1995 ST205

Also, boost control solenoids I have come across (rather limited experience here) are 3 port valves: common port connected to actuator, port which is open with no power should go to turbo, port which opens when powered should go to atmosphere.

You can test this by blowing in each port and see which 2 are connected, then connect the solenoid across the battery (after disconnecting from controller) and again see which 2 ports are connected.

Any configuration other than this will either not work or give erratic results.

_________________
If at first you don't suck seed, try drier grain.