Circuit Description

1998 Oldsmobile Achieva 3.1 M, 4T40E/MN4SECTION Circuit Description
WARNING: This page does not describe the selected car, but rather 65 other vehicles, including the 1999 Saturn SW2, 1999 Saturn SW1, 1999 Saturn SL2, 1999 Saturn SL1, and 1999 Saturn SL. However, it is still accessible from the selected car via links, so may be relevant.

PCM has internal tables that compare MAP sensor values with TP sensor values. MAP sensor is a variable resistor that responds to changes in intake manifold pressure. The voltage ranges from 1.0-1.5 volts at idle (high manifold vacuum) to 4.0-4.5 volts at wide open throttle (low manifold vacuum).

TP sensor is a potentiometer which responds to changes in throttle plate angle. At closed throttle position, output of the sensor is low (about.5 volt). As the throttle plate opens, the output signal increases so that at wide open throttle, the output will be high (about 5 volts).

DTC will set if MAP or TP sensor value is out of range for greater than 2 seconds when DTC P0107, P0108, P0122, P0123, P0506 or P0507 is set, engine speed is 1600-4000 RPM, engine speed change is less than 100 RPM, EGR commanded steady, A/C command is unchanged, and IAC change is less than 10 counts.

RENDER: 1.0x

NO RELATED

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