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exhaust temperature sensor · NGV Motori
Exhaust gas temperature sensors in diesel aftertreatment: measuring points at the catalyst, particulate filter and SCR, and replacement checks
The exhaust gas temperature sensor measures temperature at defined points in the aftertreatment system, for example upstream and downstream of the diesel oxidation catalyst, upstream and downstream of the particulate filter, and upstream of the SCR catalyst; the control unit uses these values to trigger and monitor active regeneration of the particulate filter and to release AdBlue dosing only once an effective catalyst temperature is reached.
Measuring range and construction are matched to the mounting location and the relevant engine family; a sensor upstream of the particulate filter is rated for considerably higher temperatures than a sensor at the SCR outlet. The assignment list on this page comes from official US EPA certification documentation.
A failed or sluggish sensor leads to aborted or missed particulate filter regenerations, which raises exhaust back-pressure and costs power; an incorrect temperature reading can also block AdBlue dosing, since the system assumes the catalyst temperature is too low.
Replacement is matched by part number rather than appearance, since physically identical sensors are fitted at different positions with different software; check the sensor tip and connector for damage from soot or vibration; some systems require the mounting position to be confirmed in the control unit after replacement. Price and availability are not covered on this page.
Excludes price and availability — those come from the supplier.