Skylark L4-138 2.3L DOHC VIN D MFI QUAD 4 (1989)
Crankshaft Position Sensor: Technical Service Bulletins
Engine - Revised Cranks But Will Not Run Chart
File In Section: 6E - Engine Fuel & Emission
Bulletin No.: 61-65-23
Date: May, 1996
SERVICE MANUAL UPDATE
Subject:
Section 6E3 - Driveability and Emissions - Revised Chart A-3 - Engine Cranks But Will Not Run
Models:
1988-95
Buick Skylark
1990-94
Chevrolet Beretta
1995
Chevrolet Cavalier
1987
Oldsmobile Calais
1988-91
Oldsmobile Cutlass Calais
1990-91
Oldsmobile Cutlass Supreme
1992-95
Oldsmobile Achieva
1988-95
Pontiac Grand Am
1990-91
Pontiac Grand Prix
1995
Pontiac Sunfire
with 2.3L Engine (VINs A, D, 3 - RPOs LG0, LD2, L40)
This bulletin is being issued to revise Section 6E3 of the 1987-95 2.3L engine application service manuals. The Chart A-3 Engine Cranks But Will Not
Run chart has been revised when checking for the crank sensor 5 output voltage.
The technician is directed to read the AC voltage output of the sensor at the ignition module connector while cranking the engine. If the voltage is above
a specified value, the sensor is considered OK. It has been found that a faulty sensor may still be able to generate an AC voltage higher than specified in
the diagnostic chart, causing mis-diagnosis of the ignition module.
A normal sensor generates an AC voltage of approximately 1100 mV to 1300 mV. An OK but high resistance sensor that may not cause a "Cranks But
Will Not Run" condition may generate a voltage as low as 500 mV - 600 mV.
An open sensor may generate an AC voltage of higher than the specified voltage in the step and cause a no start condition.
The following revisions should be made to the specified steps of Chart A-3 for the 1987-95 Service Manuals with OBD 1 diagnostic systems.
