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Power Fc Boost Control Unlimited Boost?


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I've recently bought a used Pfc for my r33 Gtst, also bought the map sensor, solenoid and the 3 pin wiring loom separately.

Everything is hooked up and I'm getting unlimited boost

Things I have checked:

Soldered red wire of the solenoid on to the white wire on the plug, and black to black- this should be right?

Blew through the com port on solenoid, air goes right through to the NO port when unplugged

When plugged and car idling- still blows through though with resistance

Pull out the multimeter and checked the plug, ecu side female- getting 3v on idle and constant 13v when the engine revs up a little

This explains why I'm getting unlimited boost because solenoid would've been shut the whole time

I assume that the boost controller is switched off on the PFC or otherwise I wouldn't be able to start the car according to Paulr33's guide

The PFC is the first gen, didn't come with a hand controller so I'm flying blind with the settings

Ecu wiring doesn't seem to have been touched before, other than the usual alarm immobilizer, though it was running a nissan remanufactured ECU

Solenoid is unplugged for now, so I'm just running standard boost

So question is- have I wired the solenoid wrong way round? Or is the Pfc faulty? I'm a bit hesitant in cutting the wires and resoldering it again because there's not a lot of length left. Also searched and remember someone saying that if it's wired the wrong way it just simply won't work- so you get stock boost

Any help is appreciated

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You have to turn it on or ot doesnt work. I had one and was driving with just a line to the wastegate once with the solenoid off. Then plugged it all back in and forgot to turn it on and ran 25psi of boost or something like that

You have to use the hand controller or computer software to turn it on. The hand controller makes it much easier to alter the boost settings to set it up to because it takes a bit of playing around to get it right

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It should run on wastegate duty without the actuator being pulsed.

Boost control must be setup correctly.

are you running a internal or external gate?

which ports on the external gate are plumbed to where? or how have you got the actuator connected? and where are the connected to on which ports on the solenoid?

too many variables.. take it to someone who knows what they are doing to install it for you... or this might help. its how it should be setup for a external gate single turbo setup.

INTERNAL SETUP is very different again!

post-1240-0-99886300-1390232859_thumb.jpg

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89cal's experience sounds like what I'm getting, just thought that with the boost control turned off it should run standard boost off the gate, I'll wait for the hand controller to arrive first

Btw it's standard turbo, so installation is pretty straight forward with no port to intercooler piping and com port to actuator from memory, installed an avcr on old car so not exactly rocket science

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Yup the voltage fluctuates between 2-4v on idle

Only hits steady 13.x when the throttle is open

So if I had the stock solenoid on, it would run the high boost (7psi) mode full time, which makes sense

Just going to run straight off the actuator for now, will test the boost controller again when the HC arrives, and just baby it til I get it tuned

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  • 2 months later...

so here's the update- still trying to get this to work

went away for holidays, came back and battery died

replaced battery and installed the hand controller, no more unlimited boost with boost controller function off, but with boost controller on i'm also getting standard boost (~7psi stock turbo)

realised map sensor wasn't the right one, so changed that now it reads boost perfectly fine, but still no boost control. doesn't matter how much boost and duty cycle

so brought out the multimeter, here's the result

unplugged solenoid, tested voltage, getting fluctuating voltage with B/C off, same as before

plugged it back and cut the wire between the plug and solenoid- still getting the fluctuating voltage, ie power FC is sending through voltage and the plug contact is fine

tested solenoid by directly hooking it up to battery- ticks so solenoid works

soldered the solenoid back on, tested voltage on the exposed wire before i heat shrink it- 0v with B/C on or off!

i'm pretty confused with what's happening here, everything seems to work fine but just won't work when i put them together

I've also tried adjusting the duty cycle from 50~70 on boost profile 1, 10psi/ 0.7kg/cm2, still no good

Edited by chiksluvit
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Do you think its going to get a signal when it has negative pressure? The solenoid default is normally closed, so no voltage when normally closed. With the car in vacuum its not going to want to be opening the solenoid.

Im not suprised there is no voltage there

Have you tried driving the car and seeing if it works? Remember if you have it set to 7 psi then it will cut out if it goes to around 9-10 psi so you dont need to worry too much about overboosting

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Have test driven it a lot of times and not getting any boost control, no matter how I set it, still getting standard 7psi, PFC set on 10psi

It gets voltage with BC off when engines idling, solenoid unplugged.

Plug it in and no voltage again

You're right there's no voltage when BC is turned on

I thought you're meant to get roughly 3v fluctuation during idle

Edited by chiksluvit
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Have you measured resistance through the solenoid coil? Should be resonably low.

I was pretty sure the solenoid was normally closed so if you are getting less then desired boost then it seems a bit weird. If the solenoid was wrecked it would boost till things exploded.

What are your boost settings? Do you hit boost cut at all when you put your foot down?

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no I haven't tested the resistance on the solenoid, then again i'm not really good with multimeters so I'm not sure how to check that or even what the numbers mean- anyway so here's what i've done

Electrical tests

solenoid unplugged BC on: 0.3v @ idle, fluctuates a bit when revved in neutral, can go all the way to 3v

solenoid unplugged BC off: 0.3 at idle and full 13v when revved slightly

solenoid plugged: 0v BC on or off, rev or idle, the +ve side is constantly getting the 13v, so just the ground side not grounding when its supposed to.

like as if the PFC knows i've got the solenoid connected and decides to not work caus it didn't like the solenoid

Plumbing

Its stock internal gated turbo, so plumbing's different to the diagram. I'm very sure the solenoid is plumbed right, plumbed the AVCR on my old car the same way according to apexi's instruction and it worked, NO to intercooler piping and COM to actuator, NC left out; so according to guilt-toy's diagram it would be port 2 to actuator, port 3 to intercooler piping

Driving and PFC setting

redlined the car a few times, no boost cut, max boost is 0.55, thats 7~8 psi, won't go over 0.6kgcm2

tried running the boost signal directly from intercooler pipe to the actuator, same result- this suggests the solenoid was not working at all

it's currently set at 0.7kgcm2, duty cycle 50. Have tried both 0.7kgcm2 and 1kgcm2 with duty cycle ranging from 40~90 in both boost settings, yet no difference

everything else on the PFC is fine, i can change the AFM setting it'll run like crap, fuel and ign map's been tuned and it drives nicer than before, change the idle rpm and engine responds, no other problems other than the annoying fact that BC won't work

Other things I've tried

funny how it all started with unlimited boost before i got my FC commander, turned BC on after I got the FC commander and I then get standard boost no matter how I set it, turn it off and no more unlimited boost

tried pulling the FC commander out too and yet still standard boost, BC on or off, made no difference

Solenoid

Solenoid is normally open, if you plumb it to NO port (port 3) for internal gated turbos

It would be normally closed if you plumb it to NC port (port 1), but thats for external gated setups

Have also bought a MAC solenoid to try out, and that won't work either. Tested both of the solenoids and they would click as soon as i connect them directly to the dead battery i have sitting in my garage, still getting around 10v on that
not sure if there's anything special about the apexi solenoid? has anyone had any success running a non genuine solenoid like MAC valve on the PFC? it seems like the RX7 guys like to use them with PFC as they're cheap and does the job

it was easy on my friend's r34 GTR, plugged it in, turned BC on, and hear solenoid ticking away when the +ve pressure starts to build

my car- dead as a starfish

i'm almost at the point of giving up and just going to get a turbotech

Edited by chiksluvit
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Plumbing

Its stock internal gated turbo, so plumbing's different to the diagram. I'm very sure the solenoid is plumbed right, plumbed the AVCR on my old car the same way according to apexi's instruction and it worked, NO to intercooler piping and COM to actuator, NC left out; so according to guilt-toy's diagram it would be port 2 to actuator, port 3 to intercooler piping

[Solenoid

Solenoid is normally open, if you plumb it to NO port (port 3) for internal gated turbos

It would be normally closed if you plumb it to NC port (port 1), but thats for external gated setups

Have also bought a MAC solenoid to try out, and that won't work either. Tested both of the solenoids and they would click as soon as i connect them directly to the dead battery i have sitting in my garage, still getting around 10v on that

not sure if there's anything special about the apexi solenoid? has anyone had any success running a non genuine solenoid like MAC valve on the PFC? it seems like the RX7 guys like to use them with PFC as they're cheap and does the job

I have no experience with PFC but Mac Solenoids can replace the solenoid on most boost controllers and in fact many boost controllers just use rebadged Mac valves.

I suspect yours is plumbed wrongly. If it were a Mac valve I think you should supply boost (from your intercooler pipe) to Port 1 and run port 2 to the actuator. Can you try this? (no doubt you would have to make adjustments to the PFC). [With a Link it makes no difference if the valve is NO or NC as you just adjust the duty cycle accordingly]

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