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It sounds like the bypass valve itself could be bad (the valve on the black plastic CAC tube). Under heavy boost the pressure is blowing it open and releasing boost. It also looks like one of the only things not replaced. The white plastic check valve you broke is for the crankcase ventilation system and if it was leaking then it would cause a vac/boost leak explaining the high idle situation. It could have also bled off enough boost pressure at the time to prevent the bypass valve from fluttering as well. You could pull the bypass valve off to see if it holds vacuum and to see if it blows open easily.

The waste-gate is on the turbo itself and bypasses exhaust gasses and is controlled by the valve you did the bolt mod to. I just use standard vac-hose from the local auto parts store for everything coming off the intake manifold (BPV, CBV and FPR). Or get the silicon stuff on-line (looks like you might have some already?)

My first suggestion would be to replace any vac line that is cracked or leaking and get rid of all that mod stuff. The mods didn't fix anything as you mentioned and you want a control point for diagnosis. Print off a nice schematic of the vac lines (search this forum for some pics) and then go buy 12 feet of vac hose from the parts store and replace it all. Cheap, easy and good assurance you have no leaks. Test the bypass valve or just buy a nice new forged one and be done with it.
 

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Yes and no. That is an older set up, not sure what year but pre-06 for sure. The Evap line no longer tees into the turbo inlet but instead loops back around to the back of the throttle body. If that line is on the TB, follow it - on mine it routes over by the fuel lines over to the passenger side fender. There is a port with a green cap in-line with this hose and a check valve, then it makes a 180 degree loop around to the Evap valve buried under the MAF sensor. It then routes back by the same location at the fender and under the car to the Evap canister by the fuel tank. This is an 06 set up but if you don't have the T at the turbo then I can't see it being setup any other way. If the emissions label is still there reference that. Attached is a photo of my label for reference. If you have no check valve or Evap purge valve I would be surprised but that would certainly cause an issue. And if it is setup like this then the bolt mod does nothing.

The fact that an ECU reset "cured" the problem leads me to believe the system is all there and connected correctly. Replacing those parts you mentioned is a good place to start.
 

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I couldn't find the right fuse so I pulled all of the fuses in the box next to the battery lol
:roll:

Weather you actually reset the ECU or not, it does not appear that the concern is fixed. Did you take care of the cracked hose you found and verify the proper routing? No sense in further diagnosis until you fix what you know is broken.

I've never personally seen an ECU reset fix anything that wasn't stuck in limp mode. You might "reset" the ECU but it will learn with faulty parts and eventually be back right where it was - kind of like clearing a DTC without fixing the root cause.
 
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