lovemyseven

iTrader: (2)

Hey Guys
I've recently purchased an FD with lots of mods. I've recently noticed that the Profec B that's installed isn't doing anything to regulate boost. My car boosts to about 10-12psi no matter what I do to the dials on the controller. It's got a Pettit ECU in it, but I believe the Greddy should override correct?

Am I simply seeing waste gate pressure? Where should I start my troubleshooting? Does anyone have a similar thread saved they can direct me to?

Thank You Very Much

arghx

iTrader: (3)

might need the wastegate ported. it also depends how the boost controller was hooked up plumbing-wise

Dudemaaanownsanrx7

iTrader: (23)

Are you trying to run more boost or less

Sgtblue

iTrader: (16)

It helps to list all mods your aware of.

silent_ninja_8

iTrader: (16)

It shouldn't be a wastegate pressure because then it should only boost 7-8psi.

I would call the previous owner and ask if he had any problems with it or if he was able to change the settings. Like Sgtblue said, I'd list mods done and take some pics of the install setup so people can help you identify the problem.

4CN A1R

iTrader: (6)

i have the old style profec b and mine boosts 10psi if i have it on or off. shouldnt it boost 8 psi when off?

are they any flaws with the old style controller?(if thats the same controller the op has)

R1chard

iTrader: (1)

Assuming it is installed correctly and assuming you do not have boost creep issues, with the Profec B Spec 1 turned off and the dip switches correctly configured for a wastegate with an actuator, you should see 7-8psi with the profec OFF.

If you are seeing ~10PSI regardless.. it kind of sounds like you have the factory boost control solenoid still hooked up to the wastegate actuator. There are two nipples on the wastegate actuator, one connects to the primary turbo and the other connects to the factory boost control solenoid. You want to connect your stepper motor in between the turbo and wastegate actuator and you need to disconnect and cap off the other nipple on the actuator.

The first time I installed my Profec B spec 1 I left the second nipple connected to the stock boost control solenoid and experienced the same thing. You should also double check that the dip switches on the back of the control unit are set appropriately. The manual explains how they should be set. You can download the manual from Greddy's website.

lovemyseven

iTrader: (2)

Thanks for the responses. The car has been over-hauled by Pettit. Rebuilt motor, balanced twins, upgraded smic, ecu, etc. upgraded radiator, and a greddy profec b.

I moved the dials for high and low around and no difference. I will be tearing some parts out this weekend to get to all of the necessary things to look at and get back to this post with what I find.

Ali RX7

iTrader: (2)

anyone know how the pin setting on the back of the controller should be set up for the FD with stock twins? Thanks.

R1chard

iTrader: (1)

According to page 5 of the manual (http://www.greddy.com/img/PHP/products/pdf/687.pdf) you want to set up the dip switches as the "Actuator Type".

So set them up like this (the formatting is lost when I post to the board, pay attention to the numbers or see the pic in the manual):

up down up down
4 3 2 1

Ali RX7

iTrader: (2)

thanks man, my low setting works fine but the high setting seems to make no difference no matter what I dial it to so one of the guys mentioned maybe one of the switches may be in the wrong position.

arghx

iTrader: (3)

how exactly is it hooked up? Take a picture and mark it up with MS paint

R1chard

iTrader: (1)

well, if the low setting is actually working fine, then the high setting should work too. These Profec Spec 1's are getting old though. I ended up having to replace my Profec with another boost controller because mine would short out after a while and then I would only boost to 7 - 8lbs... and then it would magically work again... which made for rather unpredictable driving. Maybe your high setting is bad?

but I agree with arghx, take a picture or at the very least descirbe your setup and we'll be able to provide more help.

lovemyseven

iTrader: (2)

thanks for all of the input, diving into this tomorrow afternoon. I will check my pin settings as well as the hose connections.

lovemyseven

iTrader: (2)

well, finally got some things removed to get a closer look. on the primary turbo, there is a small piece of tubing that comes off of the compressor housing that has two hoses attached to it. I noticed this piece has broken off of the compressor housing. Not good. I am going to try to use jb weld to reattach it.

any thoughts?

arghx

iTrader: (3)

.

Mahjik

iTrader: (1)

Is this what you are referring to?

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/help-identify-part-im-looking-852331/

If so, those two connections are for:

* oil injection nozzles
* oil crankcase ventilation

lovemyseven

iTrader: (2)

nope, it's a small line that has a hose connected to it that runs to what I believe is the profec b stepper motor, and another hose that runs from it over to the primary turbo's actuator

lovemyseven

iTrader: (2)

sorry, the other hose runs to the actuator of the second turbo, not the first

R1chard

iTrader: (1)

Yeah man, I know which line you are talking about. I have no idea what to do when that line breaks...

He is referring to the two nipples that come off the primary turbo that in a stock setup would run to the WasteGate Control Actuator and the PreControl Actuator.

Honestly, without those two lines I don't believe you will be able to control boost or transistion. I guess if you are unable to repair it you could figure out some way of blocking it off and then find another true unmolested boost source from the primary to run those lines from.... but this is way out of my pay grade. \

You are correct though, the Profec stepper motor should be attached from the primary turbo housing and then to the wastegate actuator. The other line between the primary turbo and the precontrol actuator should be left alone.

lovemyseven

iTrader: (2)

well, after further inspection, the line didn't break off of the primary turbo. It simply is inserted into a hole. Must have worked loose over time. I thought of simply sticking it back in, but decided to put a little jb weld on it so it doesn't wiggle loose again.

hopefully this cures my boost issues.

R1chard

iTrader: (1)

cool. Assuming you have everything else connected correctly you should be set. Without that line connected correctly it is clear why you where having boost issues. Good luck and let us know how it goes!