[Mk2] [Turbo] Greddy Profec B Spec II - Boost pressure problem

[misterT]

Hi all,

As title i have the Profec B Spec II fitted to my rev2 turbo.

I've changed the turbo to a CT20b, but cant seem to get the EBC set up properly.

I noticed at one point it peaked at 1.4 (x100 kpa)

So, i thought it best to start from scratch and work my way up.

Here's how i started:

SET 0%
GAIN 5%
SET GAIN 0.65 (x100kpa)
WARNING 1.1
LIMITER 20%

Now i was expecting the boost to hit around 0.8 - 0.9 at the max, as the boost pressure (SET) is at to 0% which should mean stock boost.

But, to my surprise/horror, as i wound her up, i watched the boost shoot up to 1.3 !!! Obviously i came off the throttle very fast and didn't continue to experiment.

This is not right is it? Surely with the boost pressure turned down as far as it will go it should only give stock boost?

From what i understand SET=Boost pressure, GAIN=Boost consistency, SET GAIN=When the boost starts. So SET and GAIN are the only settings that control the actual boost pressure.

With SET and GAIN set to their lowest settings, surely i shouldn't be hitting 1.3? I've heard of boost spike but thats ridiculous!

Have i missed something here?

Any help is much appreciated, thanks,
Dean

[DavidM]

This may help

http://www.imoc.co.uk/forums/viewtopic. ... ofec+setup

[3sgte]

it is possible that the wastegate/actuator is not functioning correctly

i would take the 2 pipes off the greddy boost solenoid and join them together then go out and see what boost you are getting if it is still high then you will know that the boost controller is not the problem

if the boost controller is found to be the problem then it is entireley possible it has gone wrong
i have got 2 faulty greddy boost controllers which will do nothing except overboost

[misterT]

it is possible that the wastegate/actuator is not functioning correctly i would take the 2 pipes off the greddy boost solenoid and join them together then go out and see what boost you are getting if it is still high then you will know that the boost controller is not the problem if the boost controller is found to be the problem then it is entireley possible it has gone wrong i have got 2 faulty greddy boost controllers which will do nothing except overboost

Thanks mate, i'll give that a go.

[misterT]

A quick update.

I though it would be easier to just turn off the boost controller, with the "OFF" option as then the built in boost gauge would still work and i could monitor it.

Result was stock boost.

I'm pressuming this means that my ebc is dead?

[Moo]

I had similar issues setting mine up and had to lower the set gain value.

I'm hitting 17psi with the following settings if it helps at all.

set = 60%
gain = 31%
set gain = 12.6 psi

A good way to test the EBC is to take off the vacuum pipe that goes to the controller in the cabin from the vacuum source in the engine bay. Connect a hand pump to it and start pumping. When it reaches the correct pressure you'll hear the solenoid start clicking. This test will confirm that the electronics and solenoid are working ok although it's not conclusive as the electronics may still be at fault.

You're not that far away from me so if you wanted to meet up I could plug your controller into my wiring and see what it does on my car.

[stiggy]

I had a Profec-B fail on me also. Same thing - it just doesn't control the boost at all. Seems a common thing unfortunately.