Can anyone explain to me what my Indy mechanic just told me? I had my S70 in today for my noraml annual state inspection and emissions testing. He had to replace the forward O2 sensor and now tells me that I have to drive the car for several miles and then bring it back in to see how many "INCOMPLETES" are left on the computer. He said that he can't run the emissions test until the computer shows only 2 'INCOMPLETES".
He told me that Volvo's are the worst for the computers and the re-setting process. he told me that japanese cars can reset afte driving only 7-8 miles but I may have to drive mine 200 miles before stuff gets cleared. Does this sound right? This is all new to me. Never heard of having to re-set the computer. I thought once the "check engine" light goes away, I am good to go.

Your mechanic is correct. Some of the 1996 850s NEVER completed the cycles and California had to change the inspection process to ignore and 1996 850s.

Your 1998 is different, it will clear in about 50-100 miles. So, drive it for a week and get it re-checked. Most scanners will tell you if the cycles are complete. You need to have 2 out of 3 completed to pass the test.
--
Klausc, a Volvoholic

Klaus,
Do I really have to do the following to a "T" to clear these darn monitors?
Just had the aft O2 sensor replaced, so I am back to square one.

General Instructions

1. No Diagnostic Trouble Codes (DTC) should be present in the ECM or TCM.

2. Fly wheel adaptation must be completed before diagnostics can run (Refer to Driving to change the flywheel status to "Ready").

3. Connect Volvo Systems Tester (VST). Enter the DIAGNOSTIC CHECK menu to verify if a trip has been completed as shown. Please Note: If using a scan tool other than the VST, different terms for reporting the same status may be displayed. 'READY' may be displayed as 'COMPLETE' and, 'NOT READY' may be displayed as INCOMPLETE'.

4. In order to insure EVAP leakage detection completion, the fuel level in the car should be above 1/4 and below 3/4 tank.

5. Air conditioning (A/C) must be off during idle periods. A/C compressor activation during the EVAP diagnostic may interrupt the EVAP test.

6. Select a suitable route where it is possible to achieve necessary speed and load conditions and occasionally stop at the side of the road safely. This needs to be done while obeying all traffic regulations and posted speed limits.

7. Important: Keep as steady a throttle pedal as possible when driving.

8. Engine temperature at start must be between + 29°C (84°F) to + 49°C (122°F). If engine temperature is below + 29°C, start engine to warm up over + 29°and then shut off. Restart engine when coolant temperature is between + 29°C and + 49°C.