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doggunracing
09-10-2004, 01:16 PM
I have a custom KA turbo setup. On first install, I had the Tial side port going to compressor outlet and it ran at the spring's 10 psi fine for months. I then put in a Profec B with the IN signal on a separate nipple at the compressor outlet. The OUT line goes to the top of the wastegate and the head unit goes to the intake manifold. Now, the boost is unlimited even with the Profec turned OFF!

What can cause this? What is happening to the air going to the solenoid when the Profec is turned off?

'97 S14 SE Turbo
09-10-2004, 02:14 PM
Did you route the lines based on Profect's instruction, or was it just some random thing?

orion
09-10-2004, 02:46 PM
Do you still have the side port connected at all? It still needs a signal...

- Brian

Hugh
09-10-2004, 02:47 PM
THats right, even with the boost controller off... the wastegate spring will still work as long as that side connection is going to the intercooler piping or compressor.

doggunracing
09-10-2004, 03:07 PM
Did you route the lines based on Profec's instruction, or was it just some random thing?



Yes, but I put the two signal ports beside each other in the hotpipe, right after the compressor, instead of one in the coldpipe. I don't think it should make that much difference, just response vs. safety.



Do you still have the side port connected at all? It still needs a signal...



Yes, the side port is still connected to the hotpipe at the compressor, right beside the signal port for the IN of the boost solenoid.



Thats right, even with the boost controller off... the wastegate spring will still work as long as that side connection is going to the intercooler piping or compressor.



I know that's how it should work, but it's not. Lines are connected as said before, and boost is not limited EBC on or off.

'97 S14 SE Turbo
09-10-2004, 03:31 PM
So, you are saying this:

Boost signal goes to the EBC, and to the top of the wastegate actuator. While the same time, you have boost signal that goes to the sideport.

Well, that's the problem right there.

doggunracing
09-10-2004, 03:33 PM
What else would cause unlimited boost, EBC on or off, given that the side port has a pressure source? There could be equal pressure at the top port, keeping the wastegate closed. How does the wastegate solenoid work? How does it block off the pressure when not on? What happens when a solenoid goes bad, could it let the pressure go to the top?

'97 S14 SE Turbo
09-10-2004, 03:41 PM
You don't want equal pressure at the top port. That would mean the wastegate won't open, and thus not limiting boost.

I'd suggest going over the install again with the directions.

doggunracing
09-10-2004, 03:43 PM
So, you are saying this:

Boost signal goes to the EBC, and to the top of the wastegate actuator. While the same time, you have boost signal that goes to the sideport.

Well, that's the problem right there.



No, this is how it is set up, just that instead of the side port signal from the intake manifold, it comes from the compressor outlet.

Profec B setup (http://www.wideopenwest.com/~kbounds/ProfecB%20setup.jpg)

1 goes to the EBC headunit, 2 goes to wastegate solenoid IN signal port and 3 goes to wastegate solenoid OUT port.

doggunracing
09-10-2004, 03:45 PM
You don't want equal pressure at the top port. That would mean the wastegate won't open, and thus not limiting boost.



I know that, I'm saying that is what seems to be happening, since boost isn't being limited, EBC on or off. Therefore, I was asking what could cause that situation to happen. What happens when a solenoid goes bad? Is there a way to test it?

'97 S14 SE Turbo
09-10-2004, 03:58 PM
does it click when you connect the wire to the solenoid with 12v accessory on?

masterbunta
09-10-2004, 04:20 PM
Two ways to connect it:
1. Hose connected to the inside of the WG and one hose connected to the outside. THEORY, if both are connected then both inside and outside will see the same boost and thus there will be no pressure difference to open the WG. This is where the solenoid connections are very important. The solenoid will limit boost to the outside to control boost, restricting it so there will be a pressure difference and thus opening the WG. You may have the lines reversed at the solenoid.

2. connect boost to the inside of the WG, you must make sure your connected to the correct side of the solenoid, I had it wrong at first and changed it, the instructions were misleading. You must be able to blow through the solenoid at all times if you connect it this way.

klattr1
09-10-2004, 11:34 PM
here's a diagram i made of how its supposed to be installed. i have the profec b version 1 on my car and it works great. the other picture is more confusing.
http://www.ka-t.org/klattr1/greddyprofecinstall.jpg

doggunracing
09-13-2004, 09:30 AM
does it click when you connect the wire to the solenoid with 12v accessory on?



No sound at all, and I have 12 volts up to that connector. So, the solenoid is dead? I opened it up to check the connections were good, but they're foam wrapped at the connections. Nothing looks loose though. Can I fix it? Is there a replacement short of a whole new EBC?

Enthalpy
09-13-2004, 09:35 AM
there is no click from Profec B Spec1. they run a stepper motor not a solenoid.

doggunracing
09-13-2004, 10:09 AM
there is no click from Profec B Spec1. they run a stepper motor not a solenoid.



The HKS EVC EZ, EVC IV, and GReddy PRofec A all use an identical stepper motor assembly. The GReddy PRofec B and Blitz SBC i-D share a common dual solenoid design, though they drive them differently. A'pexi stands alone with its single solenoid design.

doggunracing
09-13-2004, 10:54 AM
With the Power switch turned off on the Profec head unit, 12V is still being sent to the Solenoid. Is this to keep the Solenoid closed to only run off the wastegate? That seems like the only way. So, when the Solenoid dies, there's no boost control from the wastegate? Is there a way to make it failsafe to the wastegate?



Two ways to connect it:
1. Hose connected to the inside of the WG and one hose connected to the outside. THEORY, if both are connected then both inside and outside will see the same boost and thus there will be no pressure difference to open the WG. This is where the solenoid connections are very important. The solenoid will limit boost to the outside to control boost, restricting it so there will be a pressure difference and thus opening the WG. You may have the lines reversed at the solenoid.

2. connect boost to the inside of the WG, you must make sure your connected to the correct side of the solenoid, I had it wrong at first and changed it, the instructions were misleading. You must be able to blow through the solenoid at all times if you connect it this way.




Can you rewrite this using the terms in the picture (WG IN, WG OUT, SOL IN, SOL OUT)? It sounds like you're saying the same thing.

HIGHMILEHATCH
10-11-2004, 03:53 PM
I experienced this problem before. Boost would still climb even with the unit turned off. "IN" should go to a pre-throttle body source (tap charge pipe, or comp. housing). "OUT" to the top of the wastegate. Side of wastegate to intake manifold after t-body. Are you sure you have the dip switches on the back set properly?

doggunracing
10-12-2004, 12:58 AM
Pretty much concluded the solenoid was dead. Using an MBC now. http://forums.freshalloy.com/images/graemlins/frown.gif