A0111534828
P3 - Exhaust Pressure · Detroit Diesel
Pressure sensors and throttle elements in the EGR and exhaust path: function, part number and replacement checks
Differential pressure sensors in the EGR path measure the pressure drop across a measuring orifice and give the engine control unit the actual EGR mass flow as a control input; intake throttle plates deliberately narrow the intake cross-section to build up the pressure difference needed, while separate exhaust backpressure sensors monitor pressure ahead of the particulate filter or turbine. The throttle plate creates the pressure gradient, the differential pressure sensor measures it, and the control unit adjusts the EGR valve accordingly.
The part number is tied to the measuring range and connection geometry of the sensor, to the plate geometry and actuator of the throttle, and to the control strategy tuned in the engine control unit for the engine family and emission stage. Even within the same engine range, versions often differ by emission stage, because measuring range and connector pinout change with new calibrations. The assignment of part numbers to engines and machines on this page comes from official certification documentation issued by the US Environmental Protection Agency.
Soot deposits at the measuring orifice or in the pressure lines gradually distort the differential pressure reading and lead to an incorrectly calculated EGR rate, with increased nitrogen oxide levels or a rough idle; torn or porous pressure lines instead produce sudden fault codes. At the throttle plate, seized bearings or a worn actuator cause overrun or rattling on closing.
Replacement is governed by the part number, since measuring range, connector pinout and plate geometry can differ between components that look identical across engine families. Checks should cover the tightness of the pressure lines and their connectors, the condition of the plate bearing, and deposits in the measuring channel before fitting. After replacement, throttle control software often requires a base-position learning drive. Pricing and availability are not part of this page.
Fits these engines (9)
| Detroit Diesel DD13 | Heavy-Duty-Straßenmotoren |
| Detroit Diesel DD13HP | Heavy-Duty-Straßenmotoren |
| Detroit Diesel DD13TCO/HP | Heavy-Duty-Straßenmotoren |
| Detroit Diesel DD15TCO | Heavy-Duty-Straßenmotoren |
| Detroit Diesel DD16 | Heavy-Duty-Straßenmotoren |
| Detroit Diesel DD5 | Heavy-Duty-Straßenmotoren |
| Detroit Diesel DD5 Bus | Heavy-Duty-Straßenmotoren |
| Detroit Diesel DD8-F | Heavy-Duty-Straßenmotoren |
| Detroit Diesel DD8-R | Heavy-Duty-Straßenmotoren |
Excludes price and availability — those come from the supplier.
