Strange or unique boost issues?
05-09-12, 12:30 PM
#1
Strange or unique boost issues?
ok let me describe what the car is doing .
when on fullthrottle pulls the first gear say if I'm in first , the first gear wont build target boost , it stays at around 8 psi . if I have it set at 12. regardless how I mess with the power FC's primary settings . it seems to do this.
but after it reaches 4500 RPM's boost starts to build again . by the end of the rev range of said gear it will be maybe 1 or 2 psi under target boost , next gear it will reach target boost ..
now I say it like this because it does it reguardless of gear I'm in ..
if I'm in first it will do it and by the end of second its making target boost , and by third its maintaining target boost
if I'm in second by third gear its making target boost . so on so on .
If I'm in third gear at 50 mph , and I floor it boost will only go to about 7 or 8 .. by 4th i'm at target boost .
I'm not AS CLEAR AS I WISH I WERE with how everything in the boost system of this car works I have a general understanding but not near perfect ..
First I thought it was a vacuum leak so I went from start to finish and tightened and checked everything vacuum hose , and inter cooler piping alike .
then I've been trying to read every boost issue thread possible . and there's supposed to be a control solenoid for the primary ? if that is stuck or open could it cause this problem? ( I'm referring to what ever it is that the "boost / duty " controls in the power FC , the duty I mean of course . what ever it is that controls doesn't seem to be working as I turned the duty of the primary turbo up to 80% and there was no difference . I'm I'm guesstimating , and coming here for advice as to if its this? what could be broken haha . and if its the same thing for both primary and secondary , why am I building target boost up high ?
and then at the same time I don"t know if this is NORMAL , since its my first boosted car hah.
when on fullthrottle pulls the first gear say if I'm in first , the first gear wont build target boost , it stays at around 8 psi . if I have it set at 12. regardless how I mess with the power FC's primary settings . it seems to do this.
but after it reaches 4500 RPM's boost starts to build again . by the end of the rev range of said gear it will be maybe 1 or 2 psi under target boost , next gear it will reach target boost ..
now I say it like this because it does it reguardless of gear I'm in ..
if I'm in first it will do it and by the end of second its making target boost , and by third its maintaining target boost
if I'm in second by third gear its making target boost . so on so on .
If I'm in third gear at 50 mph , and I floor it boost will only go to about 7 or 8 .. by 4th i'm at target boost .
I'm not AS CLEAR AS I WISH I WERE with how everything in the boost system of this car works I have a general understanding but not near perfect ..
First I thought it was a vacuum leak so I went from start to finish and tightened and checked everything vacuum hose , and inter cooler piping alike .
then I've been trying to read every boost issue thread possible . and there's supposed to be a control solenoid for the primary ? if that is stuck or open could it cause this problem? ( I'm referring to what ever it is that the "boost / duty " controls in the power FC , the duty I mean of course . what ever it is that controls doesn't seem to be working as I turned the duty of the primary turbo up to 80% and there was no difference . I'm I'm guesstimating , and coming here for advice as to if its this? what could be broken haha . and if its the same thing for both primary and secondary , why am I building target boost up high ?
and then at the same time I don"t know if this is NORMAL , since its my first boosted car hah.
Last edited by Tem120; 05-09-12 at 12:44 PM.
05-09-12, 04:08 PM
#2
Well seeing as you're not building 10 psi in first, your transition is not happening, you have to be able to build enough boost for transition to occur. In other gears it seems you are able to build enough boost to transition but it is recovering boost slowly. This point to me as a problem with your turbo control actuator in the fact that it may not be receiving stored vacuum, pressure, or enough of either. The turbo control actuator requires both stored vacuum and pressure to actuate quickly. Double check your check valves and replace any that are broken or fail the "blow both ways" test. If you replace your check valves and still have issues, ensure your vacuum hoses are not old and broken or cracked. I suggest investing in a mityvac and checking out this website for troubleshooting and sequential turbo proper operation. http://www.autosportracetech.com/RX-...leshooting.htm
Matt
Matt
05-09-12, 04:30 PM
#3
Well seeing as you're not building 10 psi in first, your transition is not happening, you have to be able to build enough boost for transition to occur. In other gears it seems you are able to build enough boost to transition but it is recovering boost slowly. This point to me as a problem with your turbo control actuator in the fact that it may not be receiving stored vacuum, pressure, or enough of either. The turbo control actuator requires both stored vacuum and pressure to actuate quickly. Double check your check valves and replace any that are broken or fail the "blow both ways" test. If you replace your check valves and still have issues, ensure your vacuum hoses are not old and broken or cracked. I suggest investing in a mityvac and checking out this website for troubleshooting and sequential turbo proper operation. http://www.autosportracetech.com/RX-...leshooting.htm
Matt
Matt
05-09-12, 07:50 PM
#4
The turbo control actuator opening and the charge control alive opening are what consist of the "transition" from primary operation to primary and secondary. The powerfc has the ability to change the transition point to a different rpm, which merely flips the TCA actuator solenoid sooner. Now the issue is mechanical not tuning related. You have two chambers that store pressure. The vacuum chamber stores vacuum and the pressure chamber stores pressure. When the TCA actuator solenoid actuated it directs stored vacuum AND pressure to the TCA to quickly actuate it and keep it in the open position. If your chambers are not properly storing pressure, be it negative or positive, than your transition may be sluggish or not happening. Again please read the link I provided as it will help you with troubleshooting and understanding the sequential turbo operation.
Matt
Matt
05-09-12, 08:44 PM
#5
i had this problem with primary boost recently.
the precontrol/wastegate solenoids were shitty.
I swapped them out with another used set and the boost was totally different.
from 8-8-13 to
12-10-12 on both PFC and stock ecu.
I did not adjust anything in the PFC. it is a "stock" tune, as in whatever comes on it from APEXi.
the precontrol/wastegate solenoids were shitty.
I swapped them out with another used set and the boost was totally different.
from 8-8-13 to
12-10-12 on both PFC and stock ecu.
I did not adjust anything in the PFC. it is a "stock" tune, as in whatever comes on it from APEXi.
05-10-12, 09:38 AM
#6
ok my turbo transition seems to be this 8-6-then starts to build up to target boost IE 10 psi atm
cant really open up the car tomuch in the weekdays . so I cant really test it but the transition happens and its crisp you feel the surge of the second turbo , But
I'm still only boosting 8 psi on the first at best . so if the precontrol is opened up and letting boost just go right through it could be causing this? if it were the pill dont both normally go? or well maybe not.
cant really open up the car tomuch in the weekdays . so I cant really test it but the transition happens and its crisp you feel the surge of the second turbo , But
I'm still only boosting 8 psi on the first at best . so if the precontrol is opened up and letting boost just go right through it could be causing this? if it were the pill dont both normally go? or well maybe not.
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05-10-12, 12:47 PM
#8
no small leaks i'm pretty sure of that after it builds boost it will infact overboost after boost builds up and its maintained . after it builds target boost . I dont think its an exhaust leak I looked at every vacume line , every hose I've tightened and tie wraped everything
05-10-12, 09:54 PM
#9
i had this problem with primary boost recently.
the precontrol/wastegate solenoids were shitty.
I swapped them out with another used set and the boost was totally different.
from 8-8-13 to
12-10-12 on both PFC and stock ecu.
I did not adjust anything in the PFC. it is a "stock" tune, as in whatever comes on it from APEXi.
the precontrol/wastegate solenoids were shitty.
I swapped them out with another used set and the boost was totally different.
from 8-8-13 to
12-10-12 on both PFC and stock ecu.
I did not adjust anything in the PFC. it is a "stock" tune, as in whatever comes on it from APEXi.
05-11-12, 04:25 PM
#12
another thing to check is condition of the hoses that feed the precontrol and wastegate actuators.
if the hoses have swollen and pressure is bypassing the pills, you could result in similar.
also, far out possibility, double throttle is intermittent operation
if the hoses have swollen and pressure is bypassing the pills, you could result in similar.
also, far out possibility, double throttle is intermittent operation
05-11-12, 04:38 PM
#13
I remember the pil hoses being soft . so I'm not sure if its to soft when hot and causes air to bypass the pill or if they are good..
the hoses from the precontrol / waste gate were brittle and came apart when I swapped them out . I was really hoping that would do the trick. its weird because I think I checked all the hoses before I dropped the motor in . but I didn't change the precontrol as I didn't even know what it was at the time .
Last edited by Tem120; 05-11-12 at 04:40 PM.
06-23-12, 06:22 PM
#14
well I'm still having trouble with my boost issuesi finally had a free weekend to work on the car, removed the Air pump . and have a nice FOV I see the restrictor pill hoses . but where is the pill supposed to be I tried feeling them with my finger and didn't have much luck
06-23-12, 07:15 PM
#15
I got rained out ... couldn't finish But . I dont know what year my motor is its JDM , and didn't really have a guide .
I know the 95 year turbos had a built in restrictor pill , BUT I dont knwo what it would look like .
does anyone have pictures? ( couldnt take the little hoses off yet , but just so I know what to look for .) Will the pill be mid hose? or on one of the edges? I gave a preliminary feel and didnt feel any pill but it wasnt very good . tomorrow I'm taking the hoses off
Also just so I get this right when the car is turned off , both the waste gate , and pre control actuators are CLOSED correct?
I know the 95 year turbos had a built in restrictor pill , BUT I dont knwo what it would look like .
does anyone have pictures? ( couldnt take the little hoses off yet , but just so I know what to look for .) Will the pill be mid hose? or on one of the edges? I gave a preliminary feel and didnt feel any pill but it wasnt very good . tomorrow I'm taking the hoses off
Also just so I get this right when the car is turned off , both the waste gate , and pre control actuators are CLOSED correct?
Last edited by Tem120; 06-23-12 at 07:19 PM.
06-23-12, 07:19 PM
#16
my pills were only far enough in the hose to allow the hoses to slip on the turbo nipples.
if the pill is built into the nipple, pull off the hoses and look in the nipple... or take a flash picture on your phone and look at that.
i only recommend taking the hoses off the housing nipples and not off the actuators. it was a pain to get the hose back onto the precontrol actuator
also, with the intake removed you can get to the pill-hoses easily. no need to remove the airpump. i hope youre not trying to find pills in the four hoses attached to the solenoids
if the pill is built into the nipple, pull off the hoses and look in the nipple... or take a flash picture on your phone and look at that.
i only recommend taking the hoses off the housing nipples and not off the actuators. it was a pain to get the hose back onto the precontrol actuator
also, with the intake removed you can get to the pill-hoses easily. no need to remove the airpump. i hope youre not trying to find pills in the four hoses attached to the solenoids
Last edited by nismosilvia270r; 06-23-12 at 07:22 PM.
06-23-12, 07:27 PM
#17
my pills were only far enough in the hose to allow the hoses to slip on the turbo nipples.
if the pill is built into the nipple, pull off the hoses and look in the nipple... or take a flash picture on your phone and look at that.
i only recommend taking the hoses off the housing nipples and not off the actuators. it was a pain to get the hose back onto the precontrol actuator
also, with the intake removed you can get to the pill-hoses easily. no need to remove the airpump. i hope youre not trying to find pills in the four hoses attached to the solenoids
if the pill is built into the nipple, pull off the hoses and look in the nipple... or take a flash picture on your phone and look at that.
i only recommend taking the hoses off the housing nipples and not off the actuators. it was a pain to get the hose back onto the precontrol actuator
also, with the intake removed you can get to the pill-hoses easily. no need to remove the airpump. i hope youre not trying to find pills in the four hoses attached to the solenoids
and you said the pills were just far enough on the hose to let the hose go in on the turbo mani and not the actuators right?
06-23-12, 07:37 PM
#18
now that i reread your first post, you may have some issues with the PFC boost adjustments.
in MY recent case, after changing the pills, i set the boost to .8 for all settings. it under/overboosted and hit the PFC fuel cut several times during a pull.
-after some research, i realized that the boost setting doesnt do much for boost operation. it does more as a reference for the fuel cut than anything.
-adjustments to the duty control % values was needed. once i reduced the duty control values to 52% to more closely match the .8 target boost
also revisit what mrmatt said about the actuators. perhaps in first gear, the engine revs too quickly for the primary to provide enough pressure to move the TCA when the PFC tells it to.
i dont use first gear very much because its too short, but ill see how mine reacts to compare for you
in MY recent case, after changing the pills, i set the boost to .8 for all settings. it under/overboosted and hit the PFC fuel cut several times during a pull.
-after some research, i realized that the boost setting doesnt do much for boost operation. it does more as a reference for the fuel cut than anything.
-adjustments to the duty control % values was needed. once i reduced the duty control values to 52% to more closely match the .8 target boost
also revisit what mrmatt said about the actuators. perhaps in first gear, the engine revs too quickly for the primary to provide enough pressure to move the TCA when the PFC tells it to.
i dont use first gear very much because its too short, but ill see how mine reacts to compare for you
06-23-12, 07:48 PM
#19
now that i reread your first post, you may have some issues with the PFC boost adjustments.
in MY recent case, after changing the pills, i set the boost to .8 for all settings. it under/overboosted and hit the PFC fuel cut several times during a pull.
-after some research, i realized that the boost setting doesnt do much for boost operation. it does more as a reference for the fuel cut than anything.
-adjustments to the duty control % values was needed. once i reduced the duty control values to 52% to more closely match the .8 target boost
also revisit what mrmatt said about the actuators. perhaps in first gear, the engine revs too quickly for the primary to provide enough pressure to move the TCA when the PFC tells it to.
i dont use first gear very much because its too short, but ill see how mine reacts to compare for you
in MY recent case, after changing the pills, i set the boost to .8 for all settings. it under/overboosted and hit the PFC fuel cut several times during a pull.
-after some research, i realized that the boost setting doesnt do much for boost operation. it does more as a reference for the fuel cut than anything.
-adjustments to the duty control % values was needed. once i reduced the duty control values to 52% to more closely match the .8 target boost
also revisit what mrmatt said about the actuators. perhaps in first gear, the engine revs too quickly for the primary to provide enough pressure to move the TCA when the PFC tells it to.
i dont use first gear very much because its too short, but ill see how mine reacts to compare for you
i'm pretty sure it should reach target boost in first as well ..
but well its not that I got my primary at max duty cycle with I think its 98 . so it should be over boosting the primary turbo but it does nothing .
06-23-12, 10:33 PM
#20
for your comparison i have stock solenoids and in first, i push .8 until 4500, then a drop to .5 until 6500 when the secondary finally comes online.
not recommended, but have you tried disconnecting the pill hoses and carefully boosting to see if you can get higher boost with the actuators completely unpressurized?
not recommended, but have you tried disconnecting the pill hoses and carefully boosting to see if you can get higher boost with the actuators completely unpressurized?
Last edited by nismosilvia270r; 06-23-12 at 10:37 PM.
06-24-12, 10:29 AM
#21
for your comparison i have stock solenoids and in first, i push .8 until 4500, then a drop to .5 until 6500 when the secondary finally comes online.
not recommended, but have you tried disconnecting the pill hoses and carefully boosting to see if you can get higher boost with the actuators completely unpressurized?
not recommended, but have you tried disconnecting the pill hoses and carefully boosting to see if you can get higher boost with the actuators completely unpressurized?
06-24-12, 11:22 AM
#22
got them off , and no pills in them at all ..
if the motor is a 95 , and the pills are built into the manifold . how can I tell ? I tried looking in but cant really see anything
BUT lets say for arguments sake it was a 95 , and the pills were worn down . I got some new pills from a 93/4 motor and added them to the hoses like a 93/4 motor would have it wouldnt or shouldnt have any negative effects right ? as its restrictor is still the same width it just may have a second one somewhere down the line?
if the motor is a 95 , and the pills are built into the manifold . how can I tell ? I tried looking in but cant really see anything
BUT lets say for arguments sake it was a 95 , and the pills were worn down . I got some new pills from a 93/4 motor and added them to the hoses like a 93/4 motor would have it wouldnt or shouldnt have any negative effects right ? as its restrictor is still the same width it just may have a second one somewhere down the line?
Last edited by Tem120; 06-24-12 at 11:24 AM.
06-24-12, 04:20 PM
#23
BUT lets say for arguments sake it was a 95 , and the pills were worn down . I got some new pills from a 93/4 motor and added them to the hoses like a 93/4 motor would have it wouldnt or shouldnt have any negative effects right ? as its restrictor is still the same width it just may have a second one somewhere down the line?
no ill effect of having them in series, regardless of distance between the pills.