code 85 is: Canister purge (CANP) circuit failure.
Probably a bad canister purge solenoid. Disconnect the harness going into the solenoid and check voltage across the two pins.. Should be close to battery voltage. If you have a 11+ voltage drop across the connector replace the solenoid...If not I'll post up any diagrams I can find on alldata for you.
The solenoid connector won't have 12 volts across the pins. It should have VPWR but the ground for the solenoid comes from the EEC when it's deemed time to purge the charcoal cannister.
You can put a test light across the pins and run codes. Watch for the test light to flash. Also check your EVAP hoses because they tend to rot.
Canister purge solenoid is attached to the Charcoal canister. Which is on the passenger side engine compartment, down low in front, on the frame rail below the original air inlet box, looks like a black box. It traps excess fuel fumes from the intake, then sends them back to the tank. The solenoid is the odd shape piece before it attached via hose.
Check the leading from you intake to the canister, they tend too crack and rot.
The solenoid connector won't have 12 volts across the pins. It should have VPWR but the ground for the solenoid comes from the EEC when it's deemed time to purge the charcoal cannister.
You can put a test light across the pins and run codes. Watch for the test light to flash. Also check your EVAP hoses because they tend to rot.
I guess your right. Sorry for the bad info...I'm not real up on the OBD I stuff..
In obd II if it's not an actual circuit problem and just a leak you will get a p0455 or p0456...The circuit code sets when it doesn't see the right information on it's internal volt meter while grounding the circuit...
In OBD II you can command the circuit open or closed and check voltage drop that way. Guess I'm trying to relate newer car information to older cars which doesn't always work.