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Discussion Starter #1
In recent day, I got the CEL around me.
Go to Autozone to get the error code, P1110.
It is air charge bypass valve issue, maybe also being the vacuum tube leak.
So I replaced all. (This picture had been taken before I reaplced all vacuum)


After several times driving, the CEL came back. It is really suck.
So I guess the problem is located on the air charge bypass valve.
Yesterday the new one was arrived and ready to been put in.


When I took off the old bypass valve which maybe somewhere leak and put on the new.
Oh, My gosh, the size of long tube of new bypass valve is different with old one, so I can not put it in and fit with the part.

This is orignal one and lay out


Question:
I install the bypass valve with wrong direction? Or I can not put in?
Is this way right? (Please see the higher position, the new bypass valve laid on the black case)


Or this one is correct?


Thank you guys to response.
 
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Discussion Starter #2
I compared the outside width of both tube.
The shorter one is 2.6cm


Another angle to see the shorter one.



The longer is 2.7cm


Another angle to see longer one.


Is it normal for the air bypass valve about different size of both tube?
Any idea? Do I need to refund the product? Thank you.
 

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Like this:




kitechan said:
Is it normal for the air bypass valve about different size of both tube?
Any idea? Thank you.
Yep its normal! :cool:
 

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Surprisingly with an upgraded diverter valve you can do it either way.

The stock Bosch valve cannot hold the boost levels created in our cars when mounted "normally", with the air entering the bottom of the valve, so they mounted it "reverse". This allows the valve to hold a higher boost level, since the air entering the valve is pressing on the side of the piston or diaphragm, instead of directly against it.

If you mounted the stock valve in the "normal" fashion, by turning it around, you would get a boost leak, because the air pressure would be enough to force the diaphragm open from the bottom, and it would release air back into the intake.

HOWEVER... with an upgraded bypass valve like a Forge or Hyperboost, you can adjust the pressure that is held against the piston, so that the air pressing on the bottom is not strong enough to force it open, and the valve will hold full boost regardless of how it's oriented.

With the Forge valve there are different colors of springs. The green, yellow and red, all holding an increasing amount of boost by increasing the stiffness of the spring. If the valve is mounted in the same orientation as stock, the green valve is normally ok, as the pressure is pushing against the side of the piston. But, if you were to reorient it so that the bottom is aimed into your delivery pipe, then you would get a boost leak with the green spring. However, with the red spring, you should be able to hold full boost with no ill effects. You may need to stack a few washers to add some more force as well -- ideally you would observe a real boost gauge and ensure that you are still hitting full boost levels, and adjust accordingly.

There are some advantages to mounting it in the "normal" orientation instead of the "reverse" stock orientation. The most important one being speed... with air pressing on the bottom of the piston, it releases MUCH faster than if it was pressing against the side. This is because a vacuum line draws the piston up, but it takes a bit of time for this measly little tube to suck it open... having the air pressing on the bottom aids it and you get a much sharper bypass.

I personally have the Hyperboost adjustible bypass valve, and by screwing the preload down, it also creates more force against the piston, and can hold full boost when installed normally. Because of this, whenever I have my open intake installed (summers), I will mount my bypass valve "normally" for optimum performance and sound. During the winters when I have my airbox on, I can't hear the bypass valve so I would prefer that it acts more reliably, so I simply mount it in the stock "reverse" fashion.

To all you guys with open intakes and adjustible valves... TRY THIS OUT! I personally loved the sound of the bypass valve mounted "normally". There's no more chuffy sound and a much sharper "PSSH". You also get a bit of valve flutter when it releases at low pressure, when I would get a really ugly "choof" sound using the reverse orientation.
 
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Discussion Starter #6
Hi, Chris9-5
First to thank for your reponse.
In your opinion, what change can I do for this?
 

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kitechan said:
Hi, Chris9-5
First to thank for your reponse.
In your opinion, what change can I do for this?
Just instal it as in my picture :cool:
 

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Yep - nice and tight ;)
 

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Can I add that the forge unit does fit all the standard/stock delivery pipe etc
Ok its a PITA to get the forge unit in the delivery pipe hole (especially when cold), but it will go in with a bit of manipulation. No need for extra bit of pipe, and no need to send it back!
Cheers
P
 

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paolo said:
but it will go in with a bit of manipulation.
I think he's struggling a bit with this :confused:
 
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Discussion Starter #18
First, thanks for Chris information.:p
I will write down the detail about the silicone tube to ask auto store.

And thanks for paolo suggestion.
I will change another bypass valve(if I need), I will use Forge unit. :cheesy:
 
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