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For 1990-2009 cars only
Makes 🢒 Oldsmobile 🢒 1998 🢒 Intrigue 🢒 Engine 🢒 Engine Controls - 3.8L 🢒 Exhaust Gas Recirculation (EGR) System Description

Linear EGR Valve
Object Number: 14441 Size: SH

Purpose

The Exhaust Gas Recirculation (EGR) system lowers the Oxides of Nitrogen (NOx) emission levels caused by high combustion temperatures.To decrease combustion temperatures, the linear EGR valve feeds small amounts of exhaust gas back into the combustion chamber. The exhaust gases combine with the incoming air/fuel mixture to lower combustion temperatures.

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 supplies exhaust gas recirculation (EGR) to an engine independent of intake manifold vacuum. The PCM controls recirculation flow from the exhaust, through an orifice, and into the intake manifold by the linear EGR valve pintle. During operation, the PCM controls pintle position by monitoring the pintle position feedback signal. The feedback signal can be monitored with a scan tool as ACTUAL EGR POS. In normal operation, ACTUAL EGR POS should always be near the commanded EGR position ( DESIRED EGR POS). The PCM uses information from the following sensors to control the pintle position:

    • Engine Coolant Temperature (ECT) sensor.
    • Throttle Position (TP) sensor.
    • Mass Air Flow (MAF).

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

    • Warm engine operation
    • Above idle speed

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:

    • Engine stalls after cold start.
    • Engine stalls during closed throttle conditions.
    • Vehicle surges during cruise.
    • Rough idle.
    • DTC P0300 (misfire detected).

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

    • Spark knock (detonation).
    • Engine overheating.
    • Emission test failure.
    • DTC P0401.
    • Poor fuel economy.

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 EGR diagnostic trouble codes are encountered, go to the DTC tables for diagnosis.