Let me be a little more specific, when I was on the stock ecu and stock solenoid setup I could never really get my car to boost a good 10 pounds. I later found out my big 4 nipple solenoid in front of the uim was bad(wastegate/pree control?). I ended up doing a simplified sequential setup and had an hks evc 5 plugged directly into the wastegates them selfs per the directions on here. With this done the car had perfect boost patterns....until I installed the power fc. Now I'm not even sure what boost I could make on the secondary turbo because I can't put my foot down for more than a few seconds without making 15+psi on the primary(obviously not boosting the car around town under these conditions). I was told to turn the sequential system off via he commander(and did that) but things haven't changed. I've tried a bunch of tweeks to the boost controller it self with little to no change in the over boosting problem. I'm really stumped, if anyone could point me in the direction of a solution it would be greatly appreciated!!

 

Sounds like you lost a vacumn line to the wastegate and it's not seeing any pressure needed to open.

 

That was my guess as well, I'll have to take a look around under the air box. One strange thing i did notice if i go wot around 5000rpm(on second turbo) i can hit 10 psi immediately but it quickly drops back down to 6 all the way to red line.

 

Well all of the lines look to have no holes and a still firmly connected. The ecu did come from sr motor sports, does anyone know if they might program the boost levels differently?

 

Do you know anyone with a datalogit? If so just borrow that, go in and disable the powerFC boost controll settings using only your BC to control boost. If you do that and still have issues, then there is some sort of other problem going on.

Did you purchase the PFC new from SR motorsports? I do not believe they alter the boost control settings, but you can always call and ask them.

 

I got the ecu second hand from Fritz. It has a big sr motorsports sticker on it so id assume it was from them originally. Unfortunately I don't know of anyone in the area with a datalogit(honestly I'd be lost on how to use one). Do you know of a way to do it via the commander?

 

If you go into the "Settings" option on the main menu in the Commander, then to "Boost", you will see your over boost amounts and next to that is your primary and secondary solenoid duty cycle percentages. Move them down as low as you go...not sure if via the Commander it will let you go to 0% (You can in the Datalogit) but make them as low as possible.

I would also recommend setting your over boost fuel cut limits lower to you get fuel cut at 15psi (or wherever you feel your motor is in danger) so you don't blow anything while testing this out.

Other option is to simply unplug the two solenoids located behind the pressure tank bolted to the UIM.

 

The power fc should have no effect on the boost control if you have an aftemarket boost controller.
how is the boost controller hooked up?

 

If he has all stock solenoid, it should iirc.

 

Can you swap the stock ECU back in and see if boost is still the same?

Dale

 

Well I tried to bring the boost percentages down as far as possible but was only able to lower them to 20%. Even at the lower percentage my primary turbo sky rockets to 15psi and my secondary holds 7psi to red line. as per your question on how the boost controler is hooked up here is the diagram I used.

Also here is a pic of my commander, hopefully this will help in the process of finding out whats wrong.

 

The PFC has NO boost control if you have removed the stock boost solenoids. Think about it, that's the only way the PFC can do anything with boost.

It could be something crazy with timing on the PFC or something like that. But, to eliminate the PFC from the equation, pop the stock ECU back in and see if it runs like it used to.

Dale

 

Hi Justin,
As Dale said the PFC won't be able to control boost at all without the waste gate control solenoids installed properly.

Adj the boost on your manual controller and you should be fine. OR even better just cap the control and run on the spring which should be about 8 psi until you have PFS tune the PFC.

I'd reset any changes you've made to the PFC back to the base map and please tell me you initialized or reset the PFC back to the base map before driving the car

Thanks,
Fritz

 

With the stock ecu in I am now over boosting on both turbos so I guess we can rule out the power fc. Any ideas on where the issue is? With the stock ecu it doesn't go above 10psi as fast as with the power fc installed but it still hangs around 15psi. The only real difference is now my secondary turbo over boosts.

 

Hey Fritz,

Yes I reset the ecu back to the base map before driving. The car does drive much smoother now. I'm just not really sure where to go, my hks evc 5 has been working fine up until I installed the pfc the other day. I've adjusted the boost controller every which way with little to no results.

 

With an aftermarket boost controller, nothing should be having an effect on your boost except your boost controller. How do you have it connected? Have you tried removing the boost controller which should bring you down to wastegate pressure which is 6-7 psi. have you done any exhaust modifications that would increase flow?

thewird

 

Something is up with the boost controller for sure.

almost sounds like the solenoid/stepper valve failed in a closed position and the waste-gate is seeing no boost pressure to actuate.


as said, remove the boost controller from the equation and just run a line straight from the turbo outlet boost source to the wastegate.

 

I just noticed you posted the evc diagram. Did you cap off the other side of the wastegates?

thewird

 

I do have a straight through exhaust, but have been able to keep my boost at 10 with the help of exhaust restrictor plates and adjustments made to the gain values on the boost controller. I also have the other sides of the waste gates blocked off just like in the diagram. When I inspected the caps and lines everything looked to be intact.

 

Try manually pressurizing the the actuator with a handpump and see if it moves. The easiest test would be to eliminate the boost controller and hook up the actuators directly to the boost sources. That would tell you right away if the problem is your boost controller which it sounds like it is.

If you want to test your boost controller solenoid, feed it 12 volts and see if it clicks when you do. If it does you can test if the ports being opened alternate when you energize it with a handpump to see if its working as it should.

thewird

 

I'm not exactly sure I understand "hooking up the actuators to a boost source", do you have any sort of diagram?

 

Ok I've tested the boost controller with 12v d it does make the noises you described I i would assume it is functioning correctly. Is there anything else that would be wise to check? I do feel that I'm getting very close to resolving this issue but it must be something little I'm over looking.

 

I did find one major problem, the four hardlines the waste gate/pre control solenoids plug into two of them were caped but the other two were surprising open. I looped the lines with a vacume hose to close them off. Now almost everything seems to work, my primary turbo hits a hard 10psi in all gears but as the transition I i drop down to 7psi and slowly lose pressure. I guess now all is to find out what could be causing my secondary turbo not to build sufficient boost. Thank you all for your help thus far, its very much appreciated!!

 

Glad you figured it out, I was going to make a diagram in paint when I got home. Did you re-enable secondary turbo function?

thewird

 

Secondary turbo function? Is that through the commander? Now that i think about it was it wise to loop those lines together or should i have blocked them off separately?