HFS-6: Setting up the fail-safe?

[OverBoostinBeemers]

HFS-6 osa User Manual v4w

Page 6; right column, 3rd paragraph:

8-feet of two-core cable from the FCM is intended
for fail-safe purposes. It activates a low-power 3-
way solenoid valve to by-bass boost pressure to the
wastegate. In the event of a fail-safe activation,
it will lower the boost down to the mechanical fail-
safe setting. This option is normally intended for
use with a manual boost controller and some step
per-motor based electronics boost controller.

My question is, what if you are not running a MBC or a EBC? Boost is controlled through the DME in the BMW N54 engines. How would i go about hooking up a fail-safe?

Thanks in advance.

Tee

[Richard L]

If the wastergate is bypassed to the turbo outlet, no electronic controller can override it, It has to drop down to wastegate pressure.

What is a DME?

[OverBoostinBeemers]

If the wastergate is bypassed to the turbo outlet, no electronic controller can override it, It has to drop down to wastegate pressure.

What is a DME?

LOL, sorry. It's BMWs ECU...

[jamal]

You spice the boost cut wires directly to the stock BCS wiring at the ECU. Usually it's a two port solenoid, and when the signal is interrupted the solenoid will bypass boost pressure directly to the wastegate(s).

[Richard L]

Just to confirm Jamal's post, the section on the page 18 of the user manual refers to this connection (Example 1&2).

Yellow harness: Cut the BCV contoller wire from the ECU to the BCV.
- white wire to ECU side
- brown wire to the BCV side

To aviod CEL, enable the "DR-ON" link as instructed.

[Spoolin415]

Expanding on this, I'm running a MBC, so how would I have to do it to get the benefits of wastegate boost failsafe.

[Richard L]

If you are running a MBC, the only option is the MAC valve (page 19). The MAC valve bypasses the MBC during failsafe activation and drop the boost down to wastegate.

Other failsafe option offered by the HFS-6 will not work with MBC because of the mechanical nature of the MBC.

[OverBoostinBeemers]

You spice the boost cut wires directly to the stock BCS wiring at the ECU. Usually it's a two port solenoid, and when the signal is interrupted the solenoid will bypass boost pressure directly to the wastegate(s).

So then all it will be doing is reading voltage? And what boost cut wires? See the problem we may have there is that we are already tricking the ECU to think it is running Lower boost levels then it actually is so that CELs are not thrown.

[Richard L]

The ECU controls boost via a solenoid valve (BCV) by PWM'ing it. I assume your ECU (DME) does the same.

The HFS-6 can cut this connection between the ECU and the BCV upon failsafe activation.. This is done via the yellow harness:

Cut and splice as following:
- White ........... ECU side
- Browen ......... BCV side
To avioid CEL (check engine lamp), read the second half of page 18. Referring to the Dummy resisrtor.

[OverBoostinBeemers]

I just went out and bought an EVO X to add to my collection, so i'm just going to install the HFS-6 in that instead along with the GT35r Turbo Kit :)

Any pointers you wanna give me for the EVO X install???

[jamal]

I just went out and bought an EVO X to add to my collection, so i'm just going to install the HFS-6 in that instead along with the GT35r Turbo Kit :)

Any pointers you wanna give me for the EVO X install???

There's a grommet near that battery that is perfect for running the line under the car with the fuel rails. The stock washer tank is a little small for a meth tank and I would recommend something at least 2 gallons. But using the stock tank does make for a very clean installation since it all stays behind the cover.

Also that first batch of garret stock location turbos has had some issues. Like the wastegates falling off. We have an FP red, cosworth cams, and an AEM WI system in our X.

[OverBoostinBeemers]

I just went out and bought an EVO X to add to my collection, so i'm just going to install the HFS-6 in that instead along with the GT35r Turbo Kit :)

Any pointers you wanna give me for the EVO X install???

There's a grommet near that battery that is perfect for running the line under the car with the fuel rails. The stock washer tank is a little small for a meth tank and I would recommend something at least 2 gallons. But using the stock tank does make for a very clean installation since it all stays behind the cover.

Also that first batch of garret stock location turbos has had some issues. Like the wastegates falling off. We have an FP red, cosworth cams, and an AEM WI system in our X.

Thanks for the info! I wondered if Mitsubishi had us "Meth Heads" in mind when they decided to put the tank there. I was a little shock when i seen it. But i have a 6-Gallon Storage Tank and a 1 gallon primary tank being used ;)

Going with a GT35R kit, cams, and stock bottom... Until she goes BOOM!

[Richard L]

I really like your attitude to the "life cycle" of a tuned car.

[OverBoostinBeemers]

Oh Common' Richard, that could be forever, or it could be tomorrow. My point being, when i am ready to build the block is when every last lil horsey is squeezed out of that motor! There is only 1 way to find out the limits of a stock motor when no one else has stepped up to the plate. It's a shytty job, but someone's gotta do it!

[MacSTi]

I posted this in the pics thread but it would be more appropriate here...

I saw the posts about the failsafes. On the GD STi ECU's (2005) can you show me or send me a pinout where I would have the shop hook up the failsafes? I am running a Prodrive solenoid and Cobb AP tuning.

[Richard L]

I have the USDM wiring diagram for ther Subaru, I am not sure what GD STi means - let me know if the diagram is approproate for your car.

http://www.aquamist.co.uk/HFS6/Subaru/H6-05sti.gif

[MacSTi]

2005 USDM STi is a GD body style. The picture is not showing up

sslotnick@mac.com is my email Richard

[Richard L]

I have reloaded the diagram. I have also sent you a pdf version.

[MacSTi]

So the kit is installed and I am tuned. There was a major issue though.As soon as the install was complete, I was not able to be tuned because of a fan issue. So I turned the kit off to drive home on my pump map which was fine. Even if I was injecting meth on my pump map it will just run pig rich. Well, here is where it got interesting. I took it into boost going home and I overboosted tremendously (27psi) when I was tuned at 19. Came off gas and drove home in vacuum until my tune thinking a vacuum line came off. Today, he looked at all the lines and pressure tested the waste gate to make sure it wasn't anything like that. Did the first pull on the dyno and boom (27psi) same thing. Turned boost down to minimal and timing all the way down and same thing again. Stumped he looked at the directions and opened the ECU harnesses again and verified all the wiring against the diagram shown above and it was wired perfectly as shown above into pin 32. So as of this point, neither the tuner or the stock ECU has control over the boost or waste gate. He said lets try cutting the connection and reverting back to the stock way bypassing the failsafe to see how it works. Voila, it boost perfectly and I get tuned and it worked out great. My question is what needs to be done to correct the situation? Is there an issue with the ECU diagram you sent or the board? Is there something else I am missing?

[Richard L]

The HFS-6 allows you to have full control of ther failsafe trigger sensitivity.

it appeared that the trip sensitivity of failsafe is set too high. the trimmer marked "FLSF SENS".

- Fully counter-clockwise: 100mS (very sensitive - grace periofd is very short)
- Fully clockwis: 600mS (grace period is extended)

"grace period" is the system's response to a "over-shoot and under-swing" situation before the failsafe mechanism is triggered. This is relative to the WL and WH gap width.

For the time being, set the failsafe as follows:
1. "SFLSF SENS" to filly clockwise.
2. Set the SC to display 5-6 bars across at full boost and RPM.
3. Set the WL to fully counter-clockwise (almost no under-swing detection)
4. Set the WH to full clockwise (almost no over-swing detection)

Get your tuning done and then narrow the "Failsafe" window gap slowly. (#3 and #4). Perhaps 10 clicks. Once you have experienced no trip, wind the "FLSF SENS" in the counter-clock direction to decrese "grace period", ie more sensitive or quicker response to a "over-shoot and "under-shoot" situation.

[MacSTi]

I guess I have 2 questions that come out of this. The first being why was this happening when the system was turned off? The second being since I was already tuned, I am very concerned about touching a system that has already been fine tuned and possibly causing harm to a good working motor in the process. I am not 100% comfortable doing something like this when the tuner nor the OEM ECU had no control over the wastegate when the wires were hooked up. I guess I am just very nervous that I will touch something that will cause issues.

[Richard L]

When the system is turne dogg, it wil dault to low boost for safety reasons.

If you don't want this default settiing, un-link the "DHB" link so that the system does not ineterfere with your high boost pressure on the "off" position. Ensure you have a tank full of "race" gas every time the HFS-6 system is switched off.

All these questions you asked in the the user manual.

[MacSTi]

That's the thing Richard. When the unit is turned off and the wires were connected it was overboosting not low boost.

[Richard L]

I assume your car is not using the OE BCV.

Please do one thing for me, disconnect the power to the BCV and tell me if you still gets high boost. If ths is the case, there may be may hose routing mistake. The HFS6 just highlighted a serious problem.

You might argue the boost controller is wrong properly. The ECU doesn't care what duty cycle % it pumps into the BCV as long as it reached the target boost.

Let me know what happen to the boost when you remove the BCV plug.

[MacSTi]

I assume you are referring to the boost control solenoid. I have a prodrive solenoid which plugs into the OEM harness and acts like the OEM. Your asking me to unplug it and see what happens? It should revert to wastegate I assume is what you are saying.

The issue is not a hose issue because it has been working properly for the last year. It has only been a issue since the failsafe was wired into the ecu. Once we disconnected it, it worked properly again. I don't know any different way to try and explain it more clear. I wish it was as simple as here is the issue and here is how to fix it.

I mean I was also the one speaking to you from the shop Saturday and Sunday. When you called me Sunday morning I was getting ready to come home when I had the issue.

[Richard L]

I may not have explained the situation to you clearly.

Without the HFS-6 wired in ( this is your normal ECU to prodrive valve arrangment), if you unplug the harness to the prodrive valve, the boost should default to wastegate pressure -any outcome other than this - is not normal. This is regardless of how many years the system is in place and working correctly, it is still wrong.

Until you have tested this, the HFS-6's boost cut will never work properly. I am not rying to argue with you, I merely help you getting the HFS-6 failsafe working as it should.

[Richard L]

Mac,

I have done some research on the prodrive setup, here is a brief outline:

Port 1 ....... to turbo
Port 2 ....... to wastegate
Port 3 ....... vent to atmosphere

Please check you hose connections for me so that we are on the same page.

- When the BCS is in the un-energised state ............. boost = wastergate
- When the BCS is in the pulsing or energised state ........ boost is increased by ECU.

Here is where I got the information from:
1) http://forums.nasioc.com/forums/showthread.php?t=1190530&highlight=prodrive+3-port+valve
2) http://forums.nasioc.com/forums/showthread.php?t=870619

Hear from you soon - I want to get your failsafe working properly.

[MacSTi]

Just wanted to update the thread. Disconnected the boost solenoid and it is flowing properly at waste gate pressure which determines the solenoid is wired properly. I will check the ECU harness wiring tomorrow to make sure the wiring is according to the instructions.

[Richard L]

Good, so far so good. Mechanically sound on the hose porting to the BCS.

Just need to trace the same BCS pulse wire all the way to the ECU and splice it there.

[Richard L]

All cleared up and working 100%. There has been just some wiring issues.