The blue EVAP check valves are a common fail item on the First Generation Saab 9-5. Either one or both of these valves will fail. This will cause for lower boost. Instead of the needle making it to the red area on the turbo gauge it will only go to mid-yellow. These valves are in a hard plastic line and are difficult to replace by themselves. The line as a whole can run $300-400. The quick fix is the bolt mod which will block off this line and stop the boost leak. The con of the bolt mod is the bolt in a line right next to the BCV. If you ever want to sell the car, it could be a turn off to prospective buyers. It also isn't the way the car was designed. This method will fix the problem by replacing the valves with aftermarket valves and replace hard plastic line. This will allow a serviceable line if a check valve fails again. The greatest thing is it can be completed for under $25.
Parts Required:
-2 one way 5/16" fuel check valves (commonly found on ebay and amazon. I bought these from ebay: https://goo.gl/Esm6PY
-5 feet of 5/16" fuel line. I used rubber fuel line from napa since it is reinforced. Here is a link from ebay for what you will need: https://goo.gl/UOsKGf
-6-8 hose clamps for 5/16" line. A link for these from ebay: https://goo.gl/LcRZbs
-May need throttle body o-ring: https://goo.gl/tijztS
Tools:
-Flat head screw driver
-pliers
-long needle nose pliers (maybe angled)
-knife or something to cut the fuel line
-10mm socket and wrench (potentially 6" extension)
Process:
Step 1. Remove the Mass Airflow sensor and tube going to the Turbo cobra pipe. There are three clamps to loosen the MAF and tube. It will then pull off. This is also a good time to remove the plastic cover over the intake manifold and dipstick.
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Step 2. You will now have room to start removing the line with the check valves. There is a hose clamp holding the line onto a "T" on the hose that connects to the top port of the BCV. Slide the clamp back using pliers and the line will pull off of the T.
![Image]()
Step 3. Remove the EVAP Purge valve hose from the check valve line. There is a "T" in between the two check valves with a hose leading to the purge valve. Move the hose clamp with pliers and the hose will pull off of the T.
![Image]()
Step 4. Move the power steering pump reservoir a little for clearance. You will need to use a 10mm socket to remove the bolt and band holding the reservoir in place. Once the metal band is removed, the reservoir can move a couple of inches towards the engine.
![Image]()
![Image]()
Step 5. This is the most challenging part. The hard line has a connection into a short rubber hose going into the back of the throttle body. You may get lucky and be able to remove the clamp for the hose with long angled needle nose pliers. I tried and tried and figured it would be easier to take the throttle body off. If you take the throttle body off, you will want to replace the o-ring that is between the throttle body and intake manifold. Removing the charge pipe was all I needed to remove from the throttle body. I tilted it forward and had access to the clamp for this line. The throttle body has 3 10mm bolts that hold it on to the intake manifold and two bolts hold a metal bracket to the side for the limp home mode actuator. You will need to remove that bracket to remove the throttle body. I attached my new rubber line to the throttle body instead of having the rubber hose that came stock to attach to the hard plastic line. A clamp with a screw/bolt is easier to access here than the compression.
Step 6. Assemble the new line. The check valve on the intake manifold side will flow air towards the intake manifold. The check valve on the BCV side will flow air towards the BCV. The "T" for the hose to the EVAP Purge valve will be in the middle. The T is a little bigger than 5/16", but I was able to push the 5/16" line onto it.
Arrow on check valve:
![Image]()
![Image]()
Step 7. install the line. I used a clamp on the intake manifold side and BCV side as well as around the valves. I routed the line behind the power steering reservoir and zip tied all of the hoses in the area together.
Behind the intake manifold:
![Image]()
Behind the power steering reservoir:
![Image]()
The valve near the BCV. I tucked it under the radiator support:
![Image]()
At the BCV:
![Image]()
Old line and valves. Only one valve was bad, the one on the intake manifold side:
![Image]()
![Image]()
This took me about an hour to do including taking the throttle body off. It would be quite a bit quicker without needing to do that.
Parts Required:
-2 one way 5/16" fuel check valves (commonly found on ebay and amazon. I bought these from ebay: https://goo.gl/Esm6PY
-5 feet of 5/16" fuel line. I used rubber fuel line from napa since it is reinforced. Here is a link from ebay for what you will need: https://goo.gl/UOsKGf
-6-8 hose clamps for 5/16" line. A link for these from ebay: https://goo.gl/LcRZbs
-May need throttle body o-ring: https://goo.gl/tijztS
Tools:
-Flat head screw driver
-pliers
-long needle nose pliers (maybe angled)
-knife or something to cut the fuel line
-10mm socket and wrench (potentially 6" extension)
Process:
Step 1. Remove the Mass Airflow sensor and tube going to the Turbo cobra pipe. There are three clamps to loosen the MAF and tube. It will then pull off. This is also a good time to remove the plastic cover over the intake manifold and dipstick.
Step 2. You will now have room to start removing the line with the check valves. There is a hose clamp holding the line onto a "T" on the hose that connects to the top port of the BCV. Slide the clamp back using pliers and the line will pull off of the T.
Step 3. Remove the EVAP Purge valve hose from the check valve line. There is a "T" in between the two check valves with a hose leading to the purge valve. Move the hose clamp with pliers and the hose will pull off of the T.
Step 4. Move the power steering pump reservoir a little for clearance. You will need to use a 10mm socket to remove the bolt and band holding the reservoir in place. Once the metal band is removed, the reservoir can move a couple of inches towards the engine.
Step 5. This is the most challenging part. The hard line has a connection into a short rubber hose going into the back of the throttle body. You may get lucky and be able to remove the clamp for the hose with long angled needle nose pliers. I tried and tried and figured it would be easier to take the throttle body off. If you take the throttle body off, you will want to replace the o-ring that is between the throttle body and intake manifold. Removing the charge pipe was all I needed to remove from the throttle body. I tilted it forward and had access to the clamp for this line. The throttle body has 3 10mm bolts that hold it on to the intake manifold and two bolts hold a metal bracket to the side for the limp home mode actuator. You will need to remove that bracket to remove the throttle body. I attached my new rubber line to the throttle body instead of having the rubber hose that came stock to attach to the hard plastic line. A clamp with a screw/bolt is easier to access here than the compression.
Step 6. Assemble the new line. The check valve on the intake manifold side will flow air towards the intake manifold. The check valve on the BCV side will flow air towards the BCV. The "T" for the hose to the EVAP Purge valve will be in the middle. The T is a little bigger than 5/16", but I was able to push the 5/16" line onto it.
Arrow on check valve:
Step 7. install the line. I used a clamp on the intake manifold side and BCV side as well as around the valves. I routed the line behind the power steering reservoir and zip tied all of the hoses in the area together.
Behind the intake manifold:
Behind the power steering reservoir:
The valve near the BCV. I tucked it under the radiator support:
At the BCV:
Old line and valves. Only one valve was bad, the one on the intake manifold side:
This took me about an hour to do including taking the throttle body off. It would be quite a bit quicker without needing to do that.
