1985-1998 [Subscribe to Daily Digest] |
Your car has a Traction control problem. Is the TCS CTRL(and possibly Anti lock) lamp on? If so, it should be diagnosed by the dealer, they deal with TCS problems every day.The valve on the fender well is called the isolater valve. It's job is to disconnect the Air By pass valve(aka hooter valve)during TCS activation(wheel spin) and when the cruise control is activated. Aparently, there is a drivability issue if the bypass valve is not disconnected during the above events, however i have not experienced it. The isolater valve will not cause the system to enter limp home mode. The safety valve and the isolater valve electrical and mechanical function is identical. You can test the safety valve electrical and mechanical function by applying vacuum to the port that goes to the intake manifold and plug the port that goes to the throttle housing(while energizing the valve). Submerge that part of the valve in water and look for air bubbles. If good, no bubbles should be present. Or, try swaping the safety valve with the isolater valve to see if the problem persists.
If your car has a permanent fault, your car will go into limp home immediately after starting the engine after making a repair attempt. Intermittent faults can go away after cycling the ignition if the problem was fixed.
I would also check all the vacuum lines for the TCS system, throttle housing, safety valve, etc.... The vacuum lines, if broken and leaking will cause the system to go into limp home, just like a bad safety valve. The plastic one way valve (connected inline between the safety valve and the intake manifold) will also cause the car to enter limp home(it causes a vacuum leak). It can be tested the same way as described above. However, it should not hold vacuum on the side thats connected to the intake, only the side thats connected to the safety valve. Again, pull a vacuum on the valve and submerge in water and check for air bubbles.
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.
![]() |
![]() |
![]() |
![]() |
![]() |