Fault Condition
WARNING: This page is about a different car, the 1996 Volvo 850. However, it is still accessible from the selected car via links, so may be relevant.
The PAIR system pump is checked by disabling the long-term fuel trim and Canister Purge (CP) valve control. The PAIR system pump is started and the PAIR system valve is opened. If the short-term fuel trim integrator does not rise above a set value within 6 seconds DTC 448 (PAIR system pump flow fault) is stored.