Boost only going to 6psi
04-26-11, 11:51 AM
#1
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Boost only going to 6psi
When I bought the car I was told it was boosting 5psi, he stated he brought it to Pettit and they informed him. He said they didn't have time to put it back to 10psi but has no clue how or why they did it.
The car is almost stock except crappy intake, and 160 switch as far as I can tell. I took the lines off and verified the restrictor pills are in here, I also suspected the cat to be clogged. Today I had a mid pipe put in and it is still boosting 6 psi, although it feels like it is a bit quicker than before that could just be me.
I had a boost and water temp gauge installed and boost goes up to 6psi and water temp stays at 180 in any driving. There is no boost controller, stock ecu and pills, does anyone have a reason I would only be getting 6psi?
I checked for leaks and also had dragon motorsports check it, didn't find any but something might have been over looked. My vacuum when warm is sitting right around 15 and around 17-18 when cold. Any information would be helpful or any thing else to check.
I am going to call Pettit also to see if they remember anything about it, the car runs good and pulls good just not where it is supposed to be.
Thanks
Gary
The car is almost stock except crappy intake, and 160 switch as far as I can tell. I took the lines off and verified the restrictor pills are in here, I also suspected the cat to be clogged. Today I had a mid pipe put in and it is still boosting 6 psi, although it feels like it is a bit quicker than before that could just be me.
I had a boost and water temp gauge installed and boost goes up to 6psi and water temp stays at 180 in any driving. There is no boost controller, stock ecu and pills, does anyone have a reason I would only be getting 6psi?
I checked for leaks and also had dragon motorsports check it, didn't find any but something might have been over looked. My vacuum when warm is sitting right around 15 and around 17-18 when cold. Any information would be helpful or any thing else to check.
I am going to call Pettit also to see if they remember anything about it, the car runs good and pulls good just not where it is supposed to be.
Thanks
Gary
04-26-11, 11:57 AM
#2
I know you said you did it but Boost leak? Check all the couplers or see if you can build a pressure tester.
http://www.wonderhowto.com/how-to-ma...bo-car-265302/
http://www.wonderhowto.com/how-to-ma...bo-car-265302/
04-26-11, 02:25 PM
#5
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It is transitioning fine, just not boosting to full and it builds boost pretty quick. I am at the 6psi between 2-2.5k rpm and it is staying there without the gauge jumping around except during transition.
04-26-11, 02:26 PM
#6
Basically sounds like you are just running off the waste gate springs.
http://www.autosportracetech.com/RX-...leshooting.htm
# With only the Primary Turbocharger in operation, the Wastegate is NOT actively controlled by the ECU. Once boost pressure reaches about 10 psi, the Wastegate starts to open to bypass some of the exhaust around the Turbocharger, thus slowing down the Turbocharger. The Wastegate is not actively controlled by the ECU when below 4,500 RPM. The Wastegate solenoid is put in a fixed high duty cycle, (95% of the time on) which results in most of the air being vented from the Wastegate Actuator. At about 8 psi the Wastegate Actuator starts to move and by 10 psi the Actuator has moved enough to regulate the boost pressure to 10 psi. If boost is at 6 - 7 psi the pill to the wastegate could be missing, the Wastegate solenoid is not operating at 95% duty cycle, or the Wastegate is not mechanically connected to the actuator.
# Another problem is that the Wastegate door is slightly ajar robbing exhaust for the Primary Turbo. The solution is in properly setting the length of Wastegate Actuator rod. Disconnect the rod from the the door by removing the C-clip, hold the door closed and set the length of the rod so that one half of the arm pin is hidden by the hole in the rod end. Then reattach the rod, you will have to pull on the rod in order to get the hole to go over the pin of the arm. Remember to put that 5-7mm E-clip back on.
# The size of the pill to the Wastegate Actuator in conjunction with the fixed 95% duty cycle of the solenoid controls the maximum Primary Turbo boost pressure.
# The hose from the Primary Turbo Compressor to the Wastegate Actuator, (the one with the pill in it) can get old and can expand it's inner diameter around where the pill is, effectively creating a larger opening than the pill size for air to go through, causing lower Primary and Secondary boost.
# Another problem is that the Wastegate door is slightly ajar robbing exhaust for the Primary Turbo. The solution is in properly setting the length of Wastegate Actuator rod. Disconnect the rod from the the door by removing the C-clip, hold the door closed and set the length of the rod so that one half of the arm pin is hidden by the hole in the rod end. Then reattach the rod, you will have to pull on the rod in order to get the hole to go over the pin of the arm. Remember to put that 5-7mm E-clip back on.
# The size of the pill to the Wastegate Actuator in conjunction with the fixed 95% duty cycle of the solenoid controls the maximum Primary Turbo boost pressure.
# The hose from the Primary Turbo Compressor to the Wastegate Actuator, (the one with the pill in it) can get old and can expand it's inner diameter around where the pill is, effectively creating a larger opening than the pill size for air to go through, causing lower Primary and Secondary boost.
Last edited by RXtacy; 04-26-11 at 02:30 PM.
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04-26-11, 02:34 PM
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Basically sounds like you are just running off the waste gate springs.
http://www.autosportracetech.com/RX-...leshooting.htm
http://www.autosportracetech.com/RX-...leshooting.htm
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04-26-11, 07:21 PM
#9
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Yes sequential, I could be wrong but today after the mid pipe was installed it seemed to jump every once in awhile. This was while not in boost, probably in my head, I am gonna start to check some stuff tomorrow. I hope it isn't down long, hate driving my DD a rustang.
06-23-11, 08:58 AM
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Haven't had much time to get to the bottom of the problem, yesterday I took the UIM off to change my intake temp sensor (was pulling a code 11 and running really bad and dropping in RPMs at a stop and smoking). In the process I broke a check valve, today I put the new check valve and took it for a drive. All problems cleared up except the boost, while I had the UIM off I noticed that a hose wasn't there, I am sure it is just emissions but could anyone confirm? I have the diagram but I don't trust myself.
06-23-11, 11:58 AM
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I know why mine is just haven't lifted it to get to the rod. The butterfly to the turbos was adjusted and does not fully close. Mine was set like this and can easily be fixed. If yours just started doing it for no reason it is most likely a different problem.
07-07-11, 04:15 PM
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I figured out the problem, had a few vacuum lines not hooked up. Namely the wastegate control and turbo precontrol. Hooked it all up today and it boosted to 12psi in primary and spiked to 14psi on the secondary. Thank god I installed the Pettit ECU before fixing the problem. Now I need to restrict the exhaust some and put my boost controller in. I have to say the difference between 7psi and 12psi is just insane, I didn't get to much in it today because it rained earlier just tested 2nd gear to see where boost was. My wife is going to HATE the car now as she was already scared by it at 7psi.
07-07-11, 09:26 PM
#15
The restrictor plate in the exhaust will still allow boost creep. I did that, but would never waste my time with that again.
Do it right and yank off the turbos. Take the exhaust manifold apart and port the wastegate. Way better than restricting power/response/heat and still getting boost creep. The process seems like a chore, but it really isn't that bad.
Props to Rxtacy for nailing the problem.
Good Luck!
Do it right and yank off the turbos. Take the exhaust manifold apart and port the wastegate. Way better than restricting power/response/heat and still getting boost creep. The process seems like a chore, but it really isn't that bad.
Props to Rxtacy for nailing the problem.
Good Luck!
07-07-11, 09:34 PM
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Hahaha my wife always closes her eyes, one hand over eyes, one hand on the 'o ****' handle.
This is when I'm going about 40 mph. Apparently 40 mph in the RX7 is faster than 40 mph in her CRV.
This is when I'm going about 40 mph. Apparently 40 mph in the RX7 is faster than 40 mph in her CRV.
07-08-11, 07:28 AM
#17
When this was unplugged my primary turbo would not boost more than 6psi but the secondary would kick in fine.
This would lead me to believe your pre-control is not functioning properly.
-Geoff
07-08-11, 07:52 AM
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This right here makes me thing it's the tubo pre-control solenoid. While attempting to diagnose my boost issue one of our trouble-shooting steps was to unplug the turbo pre-control solenoid.
When this was unplugged my primary turbo would not boost more than 6psi but the secondary would kick in fine.
This would lead me to believe your pre-control is not functioning properly.
-Geoff
When this was unplugged my primary turbo would not boost more than 6psi but the secondary would kick in fine.
This would lead me to believe your pre-control is not functioning properly.
-Geoff
07-08-11, 08:41 AM
#19
I figured out the problem, had a few vacuum lines not hooked up. Namely the wastegate control and turbo precontrol. Hooked it all up today and it boosted to 12psi in primary and spiked to 14psi on the secondary. Thank god I installed the Pettit ECU before fixing the problem. Now I need to restrict the exhaust some and put my boost controller in. I have to say the difference between 7psi and 12psi is just insane, I didn't get to much in it today because it rained earlier just tested 2nd gear to see where boost was. My wife is going to HATE the car now as she was already scared by it at 7psi.
Being low to the ground does give you more of feeling of speed, but c'mon 40 mph?
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