After driving 400 miles in a 98 Volvo S70 T5, the OBD2 readiness monitors still haven’t set. While some suggest allowing the car’s computer to “settle,” experience and online forums indicate the ECU should adjust within a few miles after a reset or remap. True fuel economy improvements should be verified with actual mileage calculations, not just relying on the onboard computer. Accurate measurement requires comparing fuel consumed against known distances, considering factors like tire wear and odometer accuracy.
Several possibilities could explain why the OBD2 monitors aren’t setting. A persistent fault in the emissions system might prevent the monitors from completing their diagnostic cycles. Alternatively, a problem with the OBD2 system itself, such as a faulty sensor or wiring issue, could be the culprit. It’s also possible a recent repair or modification wasn’t performed correctly, interfering with the monitor setting process.
To troubleshoot this issue, start by checking for any stored Diagnostic Trouble Codes (DTCs) using an OBD2 scanner. Addressing these codes and any underlying mechanical problems might resolve the issue. If no DTCs are present, carefully inspect the wiring and connectors related to the emissions and OBD2 systems. A professional mechanic with Volvo experience can use diagnostic software to monitor the readiness status in real-time and pinpoint the problem area.
While waiting for the monitors to set can sometimes work, 400 miles is excessive. Further investigation is necessary to identify the root cause. Returning to the mechanic who performed the remap or reset is recommended. They can review their work and ensure no errors were made. Open communication between the vehicle owner and the mechanic is crucial for a satisfactory resolution. A thorough diagnosis and proper repair are essential to ensure the vehicle’s emissions system functions correctly and passes inspection.
