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For 1990-2009 cars only
Makes 🢒 Oldsmobile 🢒 2001 🢒 Aurora 🢒 Engine 🢒 Engine Controls - 3.5L 🢒 Exhaust Gas Recirculation (EGR) System Description

Linear EGR Valve
Object Number: 14441 Size: SH

Purpose

The exhaust gas recirculation (EGR) system is used to lower the oxide of nitrogen (NOx) emission levels caused by high combustion temperatures. The EGR system does this by decreasing the combustion temperature.

The main element of the system is the linear EGR valve. The EGR valve feeds small amounts of exhaust gas back into the combustion chamber. With the fuel/air mixture diluted by the exhaust gases, the combustion temperatures are reduced.

Operation
Object Number: 11696 Size: SH
(1)Cap-Sensor
(2)Sensor-EGR Pintle Position
(3)Pole Piece-Primary
(4)Bobbin and Coil Assembly
(5)Sleeve-Armature
(6)Valve-Pintle
(7)Armature and Base Assembly

The linear EGR valve is designed to accurately supply EGR to an engine independent of the intake manifold vacuum. The valve controls the EGR flow from the exhaust to the intake manifold through an orifice with a PCM controlled pintle. During operation, the PCM controls the pintle position by monitoring the pintle position feedback signal. The feedback signal can be monitored with a scan tool as the Actual EGR Position. The Actual EGR Position should always be near the commanded EGR position ( Desired EGR Position). The PCM uses information from the following sensors to control the pintle position:

    • The engine coolant temperature (ECT) sensor
    • The throttle position (TP) sensor
    • The mass air flow low (MAF) sensor

The linear EGR valve is usually activated under the following conditions:

    • A warm engine operation
    • An engine speed above idle

Diagnosis
Object Number: 11699 Size: SH
(1)Linear EGR Valve
(2)Exhaust Gas
(3)To Cylinders
(4)Pintle

Too much EGR flow at idle, cruise, or cold operation may cause any of the following conditions to occur:

    • The engine stalls after a cold start
    • The engine stalls during closed throttle conditions
    • The vehicle surges during cruise
    • A rough idle
    • A DTC P0300 (misfire detected) is set

Too little or no EGR flow may allow combustion temperatures to become too high. This could cause the following symptoms:

    • A spark knock
    • An engine overheat
    • An emission test failure
    • A DTC P0401set
    • Poor fuel economy

An EGR flow diagnosis is included in the DTC P0401 diagnostic table. Pintle position error and control circuit diagnosis is covered in DTCs P0403, P0404, P0405 and P1404. If any EGR diagnostic trouble codes are encountered, go to the DTC tables for diagnosis.