Spark Plugs
WARNING: This page is about a different car, the 2001 Saab 9-5 and 2001 Saab 9-3. However, it is still accessible from the selected car via links, so may be relevant.
Spark plugs play an important part in controlling timing, turbo charge and throttle position because they are used as sensors in the combustion chambers. To check for proper operation of spark plugs, remove ignition discharge module (IDM). Remove spark plugs. Inspect for deposits or damage to porcelain or electrode. Replace if necessary.