The type of probe shall be either of the following

The minimum inside diameter must be 4 mm. The minimum diameter ratio between exhaust pipe and probe must be 4.

The tip of the probe is intended to come in contact with the tissue to be examined.

The probe must extend across at least 80 % of the diameter of the exhaust pipe.

The probe must extend across at least 80 % of the diameter of the exhaust pipe.

A circuit for monitoring the condition of the probe, and indicating when replacement of the probe is desirable, is also disclosed.

The probe must extend across at least 80 per cent of the diameter of the exhaust pipe.

The minimum inside diameter of the probe tip shall be 4 mm. The minimum diameter ratio between exhaust pipe and probe shall be 4.

The probe must be replaced and the catalytic converter checked.

The temperature actuator needs to be replaced and the linkage checked.

The colorimeter should therefore automatically take care of it... normally !

The probe must be replaced and the cause for the oil burning remedied.

The clearance with the wall of the tailpipe must be at least 5 mm. The probe diameter must ensure a representative sampling and a sufficient flow through the opacimeter.

An independent reference flowmeter with a measurement range appropriate for the probe flow shall be put in series with and closely coupled to the probe.

An independent reference flowmeter with a measurement range appropriate for the probe flow shall be put in series with and closely coupled to the probe.