Sequential Owners - Can any of you make 4psi in neutral?
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Call me gramps!
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From: Detroit, MI
Sequential Owners - Can any of you make 4psi in neutral?
At WOT, 3d gear, everything stock, boost cycle is (rpm's approximate):
rpm psi 3,000 10 4,500 8 (as 2d turbo comes on) 4,500+ 10 (recovers almost immediately) 6,000+ 8 (and holds to redline)
Then here is the operation checklist developed by the Mazda Training Center in Pleasanton, CA:
93-95 RX-7 BEFORE AND AFTER SERVICE OPERATING INSPECTION STEPS SHOULD BE DONE IN ORDER. FAILURE OF ANY STEP REQUIRES FURTHER INSPECTION BEFORE CONTINUING. THESE READINGS INDICATE NORMAL OPERATION (Readings may vary with altitude and temperature)
1. CHECK FOR PCM CODES AND REPAIR AND CLEAR BEFORE ANY OTHER PROCEDURE .
2. VERIFY ENGINE IS AT OPERATING TEMPERATURE - REMOVE DOUBLE THROTTLE VACUUM LINE AT ACTUATOR - AT OPERATING TEMPERATURE NO VACUUM SHOULD BE PRESENT WITH ENGINE IDLING.
3. CHECK ENGINE VACUUM AT IDLE - REMOVE RUBBER CAP ON EXTENSION MANIFOLD - INSTALL VACUUM/PRESSURE GAUGE ON EXTENSION MANIFOLD - VACUUM READING SHOULD BE ABOVE 15" W/AC OFF
4. CHECK NO LOAD OPERATION Of TURBO - BRIEFLY ACCELERATE ENGINE TO WOT IN NEUTRAL +4 PSI SHOULD BE OBTAINED - WATCH THE PRECONTROL ROD FOR MOVEMENT
5. CHECK VACUUM TANK'S STORAGE ABILITY W/ENGINE OFF - PULL OFF VACUUM HOSE AT CHARGE RELIEF ACTUATOR - SHOULD HEAR AIR ENTERING HOSE VACUUM - START ENGINE - BRIEFLY ACCELERATE ENGINE TO WOT IN NEUTRAL AGAIN - ENGINE OFF - KOKO 6 TIMES - WATCH CHARGE CONTROL ACTUATOR WORK EACH TIME - WATCH TURBO CONTROL ACTUATOR WORK EACH TIME
6. CHECK PRESSURE TANK'S PRESSURE STORAGE ABILITY W/ENGINE OFF - PULL OFF FRONT HOSE OF PRESSURE TANK - SHOULD HEAR AIR LEAVING TANK (PRESSURE)
7. ROAD TEST WITH VACUUM/PRESSURE GAUGE INSTALLED
- DRIVE TO THIRD GEAR WITH NORMAL ACCELERATION - ACCELERATE FROM 35 MPH AT WOT UNTIL PASSING 4500 RPM - A SLIGHT AND SMOOTH INCREASE IN POWER SHOULD BE FELT AT APPROXIMATELY 4500 RPM. THIS WILL BE ABOUT 65 MPH. PRIMARY - GAUGE NEEDLE SHOULD BE ABOVE 10PSI UP TO 4500 RPM SECONDARY - NEEDLE WILL DROP TO ABOUT 8.0 PSI JUST AFTER 4500 RPM STARTS - NEEDLE WILL THEN BEGIN RISING TOWARDS MAXIMUM BOOST DEPENDING ON LENGTH OF TIME THROTTLE IS HELD. - RELEASE THROTTLE WOT = wide open throttle KOKO = Key On Key Off
rpm psi 3,000 10 4,500 8 (as 2d turbo comes on) 4,500+ 10 (recovers almost immediately) 6,000+ 8 (and holds to redline)
Then here is the operation checklist developed by the Mazda Training Center in Pleasanton, CA:
93-95 RX-7 BEFORE AND AFTER SERVICE OPERATING INSPECTION STEPS SHOULD BE DONE IN ORDER. FAILURE OF ANY STEP REQUIRES FURTHER INSPECTION BEFORE CONTINUING. THESE READINGS INDICATE NORMAL OPERATION (Readings may vary with altitude and temperature)
1. CHECK FOR PCM CODES AND REPAIR AND CLEAR BEFORE ANY OTHER PROCEDURE .
2. VERIFY ENGINE IS AT OPERATING TEMPERATURE - REMOVE DOUBLE THROTTLE VACUUM LINE AT ACTUATOR - AT OPERATING TEMPERATURE NO VACUUM SHOULD BE PRESENT WITH ENGINE IDLING.
3. CHECK ENGINE VACUUM AT IDLE - REMOVE RUBBER CAP ON EXTENSION MANIFOLD - INSTALL VACUUM/PRESSURE GAUGE ON EXTENSION MANIFOLD - VACUUM READING SHOULD BE ABOVE 15" W/AC OFF
4. CHECK NO LOAD OPERATION Of TURBO - BRIEFLY ACCELERATE ENGINE TO WOT IN NEUTRAL +4 PSI SHOULD BE OBTAINED - WATCH THE PRECONTROL ROD FOR MOVEMENT
5. CHECK VACUUM TANK'S STORAGE ABILITY W/ENGINE OFF - PULL OFF VACUUM HOSE AT CHARGE RELIEF ACTUATOR - SHOULD HEAR AIR ENTERING HOSE VACUUM - START ENGINE - BRIEFLY ACCELERATE ENGINE TO WOT IN NEUTRAL AGAIN - ENGINE OFF - KOKO 6 TIMES - WATCH CHARGE CONTROL ACTUATOR WORK EACH TIME - WATCH TURBO CONTROL ACTUATOR WORK EACH TIME
6. CHECK PRESSURE TANK'S PRESSURE STORAGE ABILITY W/ENGINE OFF - PULL OFF FRONT HOSE OF PRESSURE TANK - SHOULD HEAR AIR LEAVING TANK (PRESSURE)
7. ROAD TEST WITH VACUUM/PRESSURE GAUGE INSTALLED
- DRIVE TO THIRD GEAR WITH NORMAL ACCELERATION - ACCELERATE FROM 35 MPH AT WOT UNTIL PASSING 4500 RPM - A SLIGHT AND SMOOTH INCREASE IN POWER SHOULD BE FELT AT APPROXIMATELY 4500 RPM. THIS WILL BE ABOUT 65 MPH. PRIMARY - GAUGE NEEDLE SHOULD BE ABOVE 10PSI UP TO 4500 RPM SECONDARY - NEEDLE WILL DROP TO ABOUT 8.0 PSI JUST AFTER 4500 RPM STARTS - NEEDLE WILL THEN BEGIN RISING TOWARDS MAXIMUM BOOST DEPENDING ON LENGTH OF TIME THROTTLE IS HELD. - RELEASE THROTTLE WOT = wide open throttle KOKO = Key On Key Off
Can any of you guys make 4psi in neutral? I am having trouble building 4psi in neutral. I can only make 2-3psi if I WOT it from idle to ~7,000 RPM. Also, I am a little late on building full boost (10psi comes on at around 3,300-3,400rpm). I am thinking that it might be a small leak at the y-pipe coupler (that would be weird since it should leak more than that) or it could be that the pre-control rod/wastegate needs adjustment.
Last edited by WaLieN; Nov 1, 2004 at 06:59 PM.
Lives on the Forum
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From: San Lorenzo, California
If you don't make min 4 psi in neutral with the seq setup, there's something wrong with your car. I make 4 psi with no issues, even though I'm having a control relief/control solenoid issue at the moment.
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Originally Posted by WaLieN
How exactally did you guys "rev" the motor? Did you just WOT it from idle to redline?
Originally Posted by Mahjik
Just rev it till about 5-6000 rpms. If you can't make 4 PSI by then, something is wrong.
Oh and yea I see @ least 4 psi in neutral. Shouldn't you also be at -18 or -20 psi when the car's off? (I think...that's off memory)
Rotary Freak
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From: Slovenia, Europe
Originally Posted by FDNewbie
Mahjik, I thought the throttle is hmmm...pressure/rate sensitive? Ie, I can take my car up to redline w/o building any boost (keeping it at 0 psi). It's take a bit of practice, but I can def. do it. It comes in handy when it's raining out, being low on gas, or when it's cold in the morning and you just started driving. Basically, I'm saying it's very possible to reach 5K rpm and not build boost. You gotta get on the throttle quickly ie apply pressure *fast* do build boost. If you do it slowly, you can avoid building boost altogether.
Oh and yea I see @ least 4 psi in neutral. Shouldn't you also be at -18 or -20 psi when the car's off? (I think...that's off memory)
Oh and yea I see @ least 4 psi in neutral. Shouldn't you also be at -18 or -20 psi when the car's off? (I think...that's off memory)
I can make about 2-3psi in neutral. But I have transition issues (and sometimes no 2ndary boost in 1st or 2nd gear).
When shut off, there is no vacuum
Originally Posted by FDNewbie
Mahjik, I thought the throttle is hmmm...pressure/rate sensitive? Ie, I can take my car up to redline w/o building any boost (keeping it at 0 psi). It's take a bit of practice, but I can def. do it. It comes in handy when it's raining out, being low on gas, or when it's cold in the morning and you just started driving. Basically, I'm saying it's very possible to reach 5K rpm and not build boost. You gotta get on the throttle quickly ie apply pressure *fast* do build boost. If you do it slowly, you can avoid building boost altogether.
Oh and yea I see @ least 4 psi in neutral. Shouldn't you also be at -18 or -20 psi when the car's off? (I think...that's off memory)
Oh and yea I see @ least 4 psi in neutral. Shouldn't you also be at -18 or -20 psi when the car's off? (I think...that's off memory)
Originally Posted by Mahjik
Yes, it is load related. However, if an attempt to build boost is done using a light right foot, there are more problems than just the turbo control system.
Thread Starter
Call me gramps!
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From: Detroit, MI
Yeah, that is pretty odd that I only make 2psi in neutral. The rest of the tests are okay, and I can make ~10psi by ~3,400rpm. It trasitions and holds until redline too. What do you think could be the problem?
I went out, fully warmed it up and while it was idling, I went WOT all the way to redline. I saw 2psi of boost real quick and that was it. I tried it several times and I never saw 4psi. What can solve this problem for all of us that dont get 4psi in neutral?
Rotary Freak
Joined: Dec 2002
Posts: 2,522
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From: Slovenia, Europe
I am suspecting a small boost leak, that's why I'm planning to install a second boost gauge directly at the y-pipe.
WaLien: full 10psi on sequential (if you are) by 3400RPM is slow. I usually get full 10psi at 2800RPM, but then transition sucks at 5psi and back up to 10psi with 8psi at redline.
WaLien: full 10psi on sequential (if you are) by 3400RPM is slow. I usually get full 10psi at 2800RPM, but then transition sucks at 5psi and back up to 10psi with 8psi at redline.
Thread Starter
Call me gramps!
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From: Detroit, MI
Originally Posted by wan
I went out, fully warmed it up and while it was idling, I went WOT all the way to redline. I saw 2psi of boost real quick and that was it. I tried it several times and I never saw 4psi. What can solve this problem for all of us that dont get 4psi in neutral?
Still on 1st engine
Joined: Jun 2003
Posts: 1,176
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From: SoCal
Yeah. From a warm idle in neutral, if I stab the pedal WOT I hit 5-6psi by an indicated 5-6k. After that, I'm too afraid to keep my foot on the pedal... those last few krpm go by pretty fast.
I've got completely stock intake & exhaust... yup, even the pre-cat.
My boot pattern follows what cruiser mentioned.
I've got completely stock intake & exhaust... yup, even the pre-cat.
My boot pattern follows what cruiser mentioned.