Update on Boost Problem, and much quiter engine!!
08-23-01, 09:00 AM
#1
Lawn Ornament
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Update on Boost Problem, and much quiter engine!!
Well last night when i was messin around tryin to figure out my boost problem, i decided to unplug my air pump seeing that i am getting the pulley kit in a few days anyway. Well there was a considerable amount of noise coming from it and when i unplugged it i could barely here the engine running, sweeeeeeet!!! But anyway the boost problem is still there 
.. 11-8-5.... I moved the boost gauge over to the nipple by the CRV and it didn't ever read any boost or vacuum, even after 4500 rpm.
I know the turbo is good, what else could be the problem???
.. 11-8-5.... I moved the boost gauge over to the nipple by the CRV and it didn't ever read any boost or vacuum, even after 4500 rpm.I know the turbo is good, what else could be the problem???
08-23-01, 09:47 AM
#2
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What do you mean you moved the boost gage over to the niple near the CRV? Are you talking about the nipple on the Y-pipe closest to the fire wall?
If you Teed in to that line then you should see slight boost movement on the gauge, but not much since the CRV should be venting most of the prespool boost. After 4500 RPM you should see the gauge move toward 8 and then fall to 5 or even 0 if your secondary turbo is not working properly.
Remove the CRV hos from the air box if you have it hooked up there. Listen for the a hissing of th CRV when you are accelerating up to 4500RPM
This is the prespool venting, getting ready to spin real fast after 4500RPM.
If you do not hear the hissing, or rushing of air from under your hood then you can narrow your search down to the hose leading to the precontrol actuator from the main turbo and the hose from the precontrol actuator to the precontrol solenoid valve.
Check the wire harness on the solenoid.
Check to see that the restrictor pill is in line between the main turbo and the precontrol.
Hook up your hand pump and add pressure to the actuator (turbo side) and see if the rod moves.
Once you get that narrowed down, you could then go and test the car and see if the problem is resolved. At the least, you should hear the hissing that mentioned before.
If you still have boost problems, don't fret, you just took care of one of the problems that would prevent you from getting full boost.
You need to now deal with the Turbo Control Actuator, a slightly more ambiguous creature. The reason being is because instead of simply making it a diagnostics of point “A” to point “B”, you have a diagnostics of point “A” to point “W” plus a few sub categories. So, look on the forum for boost problems and you will see plenty of information on how to go about checking the Turbo Control Actuator system.
FYI, the Turbo Control Actuator is the heat of the secondary turbo, and it must be working to get boost on No.2.
Have fun!
If you Teed in to that line then you should see slight boost movement on the gauge, but not much since the CRV should be venting most of the prespool boost. After 4500 RPM you should see the gauge move toward 8 and then fall to 5 or even 0 if your secondary turbo is not working properly.
Remove the CRV hos from the air box if you have it hooked up there. Listen for the a hissing of th CRV when you are accelerating up to 4500RPM
This is the prespool venting, getting ready to spin real fast after 4500RPM.
If you do not hear the hissing, or rushing of air from under your hood then you can narrow your search down to the hose leading to the precontrol actuator from the main turbo and the hose from the precontrol actuator to the precontrol solenoid valve.
Check the wire harness on the solenoid.
Check to see that the restrictor pill is in line between the main turbo and the precontrol.
Hook up your hand pump and add pressure to the actuator (turbo side) and see if the rod moves.
Once you get that narrowed down, you could then go and test the car and see if the problem is resolved. At the least, you should hear the hissing that mentioned before.
If you still have boost problems, don't fret, you just took care of one of the problems that would prevent you from getting full boost.
You need to now deal with the Turbo Control Actuator, a slightly more ambiguous creature. The reason being is because instead of simply making it a diagnostics of point “A” to point “B”, you have a diagnostics of point “A” to point “W” plus a few sub categories. So, look on the forum for boost problems and you will see plenty of information on how to go about checking the Turbo Control Actuator system.
FYI, the Turbo Control Actuator is the heat of the secondary turbo, and it must be working to get boost on No.2.
Have fun!
08-23-01, 05:17 PM
#5
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spooledup7 - have you actually teed into the pressure feed for Charge Relief and Charge Control (the vac line behind CRV vent line) in a working car?
Your "theoretical" answer isn't what it actually is....
ej - get another vac/pressure gauge from Sears, $20, and vacuum line to run it into the cabin. It really helps...I had my friend reading off 4 vac gauges and several voltmeters when isolating my problems :-)
Here is what you want to do to find out boost activity:
#2 Tee into above mentioned with one vacuum gauge (2nd turbo)
#1 Tee into the pressure tank, before the check valve preferably with another vacuum gauge (1st turbo)
WOT in 3rd gear:
#1
Up until 3000rpms, 10psi (once it spools)
3000-4000'ish, drop to 7psi while 2nd turbo prespools
Onwards - 10psi (pegs my extra pressure gauge which only goes to 10psi)
#2
Zero until 3000rpms
Prespool brings it up to 10psi
4500->holds 10psi onwards
Done and done. How do you watch 4 gauges at once? Bring your mechanic friend along (his observations).
The original poster's problem is TC solenoids not working, or TCA not hooked up properly (e-clip missing), or vac line issues.
It could also be SEVERELY clogged up cat, but doubtful.
Given you get 11-8-5, it is plain and simple that you've got prespool going somewhat (otherwise, it would be 11-5-5).
I think you also may have the precontrol and wastegate solenoid electrical connectors reversed.
a.f.
Your "theoretical" answer isn't what it actually is....
ej - get another vac/pressure gauge from Sears, $20, and vacuum line to run it into the cabin. It really helps...I had my friend reading off 4 vac gauges and several voltmeters when isolating my problems :-)
Here is what you want to do to find out boost activity:
#2 Tee into above mentioned with one vacuum gauge (2nd turbo)
#1 Tee into the pressure tank, before the check valve preferably with another vacuum gauge (1st turbo)
WOT in 3rd gear:
#1
Up until 3000rpms, 10psi (once it spools)
3000-4000'ish, drop to 7psi while 2nd turbo prespools
Onwards - 10psi (pegs my extra pressure gauge which only goes to 10psi)
#2
Zero until 3000rpms
Prespool brings it up to 10psi
4500->holds 10psi onwards
Done and done. How do you watch 4 gauges at once? Bring your mechanic friend along (his observations).
The original poster's problem is TC solenoids not working, or TCA not hooked up properly (e-clip missing), or vac line issues.
It could also be SEVERELY clogged up cat, but doubtful.
Given you get 11-8-5, it is plain and simple that you've got prespool going somewhat (otherwise, it would be 11-5-5).
I think you also may have the precontrol and wastegate solenoid electrical connectors reversed.
a.f.
08-23-01, 08:18 PM
#6
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Bond, actually, no I hadn't teeded into that hose before until today to get a better understanding of what is going on.
I think that you have mistaken my earlier dialog for test results based on a "working car", when in fact I was predicting the results of what one would see in the state his car is in.
If he is not seeing any boost from that tapped line, but he is seeing 5PSI at the manifold, then it is easy to reason that the charge control door is not opening.
Make sense?
I saw a build up of boost at 4K and 12 after 4500RPM.
I think that you have mistaken my earlier dialog for test results based on a "working car", when in fact I was predicting the results of what one would see in the state his car is in.
If he is not seeing any boost from that tapped line, but he is seeing 5PSI at the manifold, then it is easy to reason that the charge control door is not opening.
Make sense?
I saw a build up of boost at 4K and 12 after 4500RPM.
08-24-01, 01:09 AM
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Ok, I reread what I just wrote, and I didn't make much sense to me. I think I was too eager to make a defensive reply. Truth is, it was only my theroy, and Bond was right about there being a measurable amount of boost built even with the CRV open, but I did not let my pride stand in front of me and I did performed the test today. My boost is normal, and here is what I saw.
Boost gauge Teed in to the charge control hose from the back of the Y-Pipe.
WOT in 3rd:
No boost at 3000RPM.
Boost begins at 4000RPM
Boost is full on past 4500 at 12PSI (WOW, what a difference between the turbo and manifold pressure!)
The main issue is still why is mjack1 only getting 5PSI after 4500RPM?
mjack1 says that the boost gauge reads nothing when teed into this hose.
What could this mean?
1. Is the precontrol working? No
2. Is the turbo control working? No
3. Is the charge control system working? No
If the precontrol was working, there would be boost
4. Is he really teed into the same hose we are talking about? I don't know.
How could we purposly make 5psi on secondary boost?
1. close the charge control door.
2. Half open the Turbo controller.
3. Swap the wastegate and precontrol wire harness. (Bond007 mentioned this)
4. Stuck shut precontrol solenoid valve.
I'm stumped on any other functions that could cause 5PSI past 4500 when you get 11 on primary.
Next?
Boost gauge Teed in to the charge control hose from the back of the Y-Pipe.
WOT in 3rd:
No boost at 3000RPM.
Boost begins at 4000RPM
Boost is full on past 4500 at 12PSI (WOW, what a difference between the turbo and manifold pressure!)
The main issue is still why is mjack1 only getting 5PSI after 4500RPM?
mjack1 says that the boost gauge reads nothing when teed into this hose.
What could this mean?
1. Is the precontrol working? No
2. Is the turbo control working? No
3. Is the charge control system working? No
If the precontrol was working, there would be boost
4. Is he really teed into the same hose we are talking about? I don't know.
How could we purposly make 5psi on secondary boost?
1. close the charge control door.
2. Half open the Turbo controller.
3. Swap the wastegate and precontrol wire harness. (Bond007 mentioned this)
4. Stuck shut precontrol solenoid valve.
I'm stumped on any other functions that could cause 5PSI past 4500 when you get 11 on primary.
Next?
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