APV Mechanism.
06-29-2007, 10:39 AM
#1
APV Mechanism.
I know we've talked about the variable intake plenum before, where it opens and where it closes, how to modify the EMU so it enables it to work but I dont recall and couldnt find a thread where we talked about the actual mechanical functioning of this feature.
I know something happens at around 4300RPM and that at 6200rpm something else happens but I dont know exactly how?
The reason I am asking is because when I was changing my injectors I noticed that although I had read that the APV was operated by a motor I did find that in the lower intake manifold there was an aluminum "valve" that when turned 90 deg. would open a path for airflow. This valve is operated with a vacuum actuator that is connected to a vacuum solenoid located under the plastic intake manifold. Which valve is this? Is this the one that opens at 4300rpm? If so I'm thinking it wouldnt be opening at all in cars with FI because it uses vacuum to operate and when the solenoid opened under boost it would actually push against it opening. I'm just looking to understand exactly how this variable intake feature works because I am exploring certain posibillities and this would help me out. Pictures are more than welcome if available.
For the people with the Interceptor;
I know this EMS has control over when the APV opens(I'm talking about the one that usually opens at 6200), has anyone opened it all the time? if so, what where the effects at idle? Any input will be appreciated. Thanks.
Chris......Esmeril
I know something happens at around 4300RPM and that at 6200rpm something else happens but I dont know exactly how?
The reason I am asking is because when I was changing my injectors I noticed that although I had read that the APV was operated by a motor I did find that in the lower intake manifold there was an aluminum "valve" that when turned 90 deg. would open a path for airflow. This valve is operated with a vacuum actuator that is connected to a vacuum solenoid located under the plastic intake manifold. Which valve is this? Is this the one that opens at 4300rpm? If so I'm thinking it wouldnt be opening at all in cars with FI because it uses vacuum to operate and when the solenoid opened under boost it would actually push against it opening. I'm just looking to understand exactly how this variable intake feature works because I am exploring certain posibillities and this would help me out. Pictures are more than welcome if available.
For the people with the Interceptor;
I know this EMS has control over when the APV opens(I'm talking about the one that usually opens at 6200), has anyone opened it all the time? if so, what where the effects at idle? Any input will be appreciated. Thanks.
Chris......Esmeril
06-29-2007, 01:22 PM
#2
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Posts: n/a
There's a check valve under the upper intake manifold on the rubber hose that leads to the vacuum block/reservoir that supplies the three solenoids, two for the SSV and VDI and the other for the airpump. As long as the check valve is good, there is no way for these units to see pressurised air.
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Last edited by GTAW; 06-29-2007 at 01:47 PM.
06-29-2007, 01:53 PM
#3
There's a check valve under the upper intake manifold on the rubber hose that leads to the vacuum block/reservoir that supplies the three solenoids, two for the SSV and VDI and the other for the airpump. As long as the check valve is good, there is no way for these units to see pressurised air.
[IMG][/IMG]
[IMG]
[/IMG]Also, in theory if using the EMU we decide to lock the APV that opens at 6200rpm on the open position(move it and unplug it) the ECU will throw a CEL but if we leave the resistor that originally came with the EMU harness connected then the ECU will think it is still working properly and wont throw a CEL? Am i right? Thanks.
Chris
06-29-2007, 02:20 PM
#4
GTAW,
I also note in the diagram you posted that what I thought to be the secondarry shutter valve is actually the VDI which doesnt do anything but equalize both sides of the intake manifold above 7200, this isnt working on my car since it is not getting any vacuum at 7200. Do you have any pictures of the lower intake manifold and what the APV and SSV look like, thanks.
Chris
I also note in the diagram you posted that what I thought to be the secondarry shutter valve is actually the VDI which doesnt do anything but equalize both sides of the intake manifold above 7200, this isnt working on my car since it is not getting any vacuum at 7200. Do you have any pictures of the lower intake manifold and what the APV and SSV look like, thanks.
Chris
06-29-2007, 02:49 PM
#6
Well, I am sure that the ones that operate with vacuum arent opening simply because there is no vacuum to open them at WOT because the car is under boost. I also know something isnt opening because the car looses power after 6500rpm which is precisely where it should kick in because of the APV. My Turbo doesnt die with rpm because its big enough, so I am gettin all this TQ and I am almost at 300whp at 6400rpm. With this Hp figure at 6400 I should be at least at 330whp at 8000-8500rpm if the APV where to open. It is really limiting me.
I would greatly appreciate the pics of the lower manifold. Thanks.
Chris
06-29-2007, 02:51 PM
#7
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Posts: n/a
Here you go...
[IMG]
[/IMG] VDI valve
[IMG]
[/IMG] SSV
[IMG]
[/IMG] VDI unit
[IMG]
[/IMG] SSV unit
I took out the whole APV assembly to make a custom lower intake, so any pictures would only show the bare bones of the manifold, it you still want them let me know.
[IMG]
[/IMG] VDI valve[IMG]
[/IMG] SSV[IMG]
[/IMG] VDI unit[IMG]
[/IMG] SSV unitI took out the whole APV assembly to make a custom lower intake, so any pictures would only show the bare bones of the manifold, it you still want them let me know.
06-29-2007, 03:03 PM
#8
[QUOTE=
I took out the whole APV assembly to make a custom lower intake, so any pictures would only show the bare bones of the manifold, it you still want them let me know.[/QUOTE]
Hi,
Send me all the pictures you can. I jsut want an idea of location so I can plan out what I am going to do. Thanks.
Chris
I took out the whole APV assembly to make a custom lower intake, so any pictures would only show the bare bones of the manifold, it you still want them let me know.[/QUOTE]
Hi,
Send me all the pictures you can. I jsut want an idea of location so I can plan out what I am going to do. Thanks.
Chris
06-29-2007, 08:04 PM
#10
Even if Petit left the "vacuum canister" it is still FI so there would be no vacuum under full throttle so they wouldnt be opening even if the solenoids where working unless they have something else we dont know about...
GTAW, where are the pics of the lower manifold?
thanks.
Chris
GTAW, where are the pics of the lower manifold?
thanks.
Chris
06-29-2007, 10:47 PM
#12
The canister operates like the brake booster; the one-way/check valve allows the storage of vaccum for use in situations where the engine has little or no vacuum signal. If your hypothesis was accurate none if the intake valves would operate under WOT regardless of boost or N/A.
Chris
06-29-2007, 11:54 PM
#14
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Yes, that's exactly what it is. This isn't from my car though...and this is actually clean compared to when I got it. Who ever was driving this car probably never went over 6000 rpms. The VDI is almost mint, poor renesis.
06-30-2007, 10:03 AM
#15
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