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2015 Ford Focus ST, big turbo, built motor
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Discussion Starter · #1 ·
Hello, all. Having some issues with my car, and unsure of the cause. (my car is built for this power level, with all supporting mods)

A little backstory swapped out my old turbo gtx3071r with a g30-660. (internal wastegate went bad, not enough top end power). Getting tuned through JST. Everything was great until one of my charge pipes popped off, after this i had this issue of lower boost. Previously on the same tune I was hitting 29.5, now I am lucky to hit 17psi. I replaced the boost control solenoid, pressure tested the system up to 45psi, no leaks. Just tested the voltages going to the solenoid, got 12VDC to the gray wire, and the blue-red one was getting 3.46VDC when the key was on, engine not running. The wastegate is a Turbosmart Compgate 40, with a 17lbs spring setup.

I also unplugged the electrical connector to the boost control solenoid, and the issue almost was the same.

Unplugging the line to the wastegate gives me 29.5lbs of boost. So I do not suspect the wastegate to be the problem. This is how i have the wastegate setup. with proper boost lines. (I replaced the lines as I though they could have been the issue, no cracks splits or tears in the old lines)
Wheel Font Engineering Automotive wheel system Auto part


Thank you everyone for the help!!
 

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I'm not an expert on topic, but 3.46V doesn't sound like a nominal voltage that you'd be looking for there? Perhaps 5V? Id laymen induce you have a voltage drop.
 

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2017 Kona Blue ST1
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This is where you need to be careful how you check voltages. Depending on your DMM you can usually check for voltage at a connector but caution must be taken or damaged to the PCM can occur.

The Gray wire is the solenoid power source voltage fed by F34 (10 amp) and the Blue/Red wire is the PWM controlled ground from the PCM. It is designed to operate with a load inline. Accidentally connecting this wire to voltage may potentially damage the PCM.

Rectangle Font Schematic Material property Parallel


The PWM (pulse width modulation) duty cycle rapidly turns the solenoid on and off to operate it. So the voltage you're see is likely negative voltage.

With everything hooked up, what is the TIP Actual vs TIP Desired?
 

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Discussion Starter · #5 ·

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Discussion Starter · #8 ·
Hello, all. Having some issues with my car, and unsure of the cause. (my car is built for this power level, with all supporting mods)

A little backstory swapped out my old turbo gtx3071r with a g30-660. (internal wastegate went bad, not enough top end power). Getting tuned through JST. Everything was great until one of my charge pipes popped off, after this i had this issue of lower boost. Previously on the same tune I was hitting 29.5, now I am lucky to hit 17psi. I replaced the boost control solenoid, pressure tested the system up to 45psi, no leaks. Just tested the voltages going to the solenoid, got 12VDC to the gray wire, and the blue-red one was getting 3.46VDC when the key was on, engine not running. The wastegate is a Turbosmart Compgate 40, with a 17lbs spring setup.

I also unplugged the electrical connector to the boost control solenoid, and the issue almost was the same.

Unplugging the line to the wastegate gives me 29.5lbs of boost. So I do not suspect the wastegate to be the problem. This is how i have the wastegate setup. with proper boost lines. (I replaced the lines as I though they could have been the issue, no cracks splits or tears in the old lines)
View attachment 405702

Thank you everyone for the help!!
Also no codes besides the catalyst system. for being catless.
 

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This is with the key on and engine off. showing TIP actual vs desired.
TIP Desired (throttle inlet pressure) is the amount of pressure (desired) by the PCM.
TIP Actual is the what is there.
These measurements are the before throttle body.

The MAP (manifold absolute pressure) is pretty self explanatory.

So the test in more of a driving and comparing the actual vs desired to see what the PCM is expecting.
 

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Discussion Starter · #11 ·
TIP Desired (throttle inlet pressure) is the amount of pressure (desired) by the PCM.
TIP Actual is the what is there.
These measurements are the before throttle body.

The MAP (manifold absolute pressure) is pretty self explanatory.

So the test in more of a driving and comparing the actual vs desired to see what the PCM is expecting.
I am assuming the So is a Do, and I did in this post.

the actual was consistently lower than the desired.

Here are the Datazap files.

Log1 is the latest revision of the tune with aux fuel. Log 2 is the base map, switched to slot 2,3 inside if the run to see if boost pressure increased, show more WGDC.


Will upload more of the previous datalogs from previous revisions of my tune.
 

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Discussion Starter · #12 ·

There are two logs in this one, both of these are with the wastegate line disconnected. So the system can make boost pressure. After doing this it makes me thing something may be wrong with the controller (just got a new one from ford) or the wires going to it. Not the smartest with the wiring issues.
 

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Discussion Starter · #13 ·
This is where you need to be careful how you check voltages. Depending on your DMM you can usually check for voltage at a connector but caution must be taken or damaged to the PCM can occur.

The Gray wire is the solenoid power source voltage fed by F34 (10 amp) and the Blue/Red wire is the PWM controlled ground from the PCM. It is designed to operate with a load inline. Accidentally connecting this wire to voltage may potentially damage the PCM.

View attachment 405703

The PWM (pulse width modulation) duty cycle rapidly turns the solenoid on and off to operate it. So the voltage you're see is likely negative voltage.

With everything hooked up, what is the TIP Actual vs TIP Desired?
Would you know what voltage that the red blue wire should read with the car on but engine not on?
 

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2017 Kona Blue ST1
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Would you know what voltage that the red blue wire should read with the car on but engine not on?
your not going to get any useful reading from that wire.
It's the control part of the circuit.

I just home and will look over the logs here in a few.
 

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Discussion Starter · #15 ·
your not going to get any useful reading from that wire.
It's the control part of the circuit.

I just home and will look over the logs here in a few.
Ok, thanks. I appreciate it!!
Do you think a bad ground could cause these issues?
 

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So the log you on post #5 (CSV2)

APP = 100 (WOT)
ETC = 82.25% (WOT)
FUEL & TIME = Good

TIP Desired = 38.94 PSI - I don't know where you are in the world so I'm just going to use 1 BAR (14.5). 24.44 PSI

TIP Actual = 25.61 PSI - 14.5 = 11.11 PSI

WGDC = 67% +/-

Are you sure that you hooked up the vacuum lines correctly?

What all charged between the time this thing ran correctly and now?

For the life of me, just how in the hell this thing isn't throwing a P0299???
 

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Discussion Starter · #18 ·
So the log you on post #5 (CSV2)

APP = 100 (WOT)
ETC = 82.25% (WOT)
FUEL & TIME = Good

TIP Desired = 38.94 PSI - I don't know where you are in the world so I'm just going to use 1 BAR (14.5). 24.44 PSI

TIP Actual = 25.61 PSI - 14.5 = 11.11 PSI

WGDC = 67% +/-

Are you sure that you hooked up the vacuum lines correctly?

What all charged between the time this thing ran correctly and now?

For the life of me, just how in the hell this thing isn't throwing a P0299???
Yep, lines are hooked up properly, The only thing that changed was the charge pipe on the cold side popped off, replaced it, and then the issue happened. Then pressure tested the system. I dont know either. this really confuses me.
 

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I doubt there is a controls issue, I had a friend with this issue and he hunted everything for awhile. He finally just went through and reseated all of his charge pipes and it took care of the problem. If one pipe came off another one could have came loose. Cause and effect here is the way I would look at it rather than jumping into other areas.
 
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