Pontiac Fiero 1988 Service Manual page 584

DRIVEABILITY AND EMISSIONS FUEL INJECTION (PORT) 6E3-A-1
SECTION A
2.8L ENGINE
BASIC PROCEDURE
if you have not reviewed the basic information on
how to use the diagnostic procedures, go to the
introduction of this section. The facing page of each
chart in this section will provide a general circuit
description and in some instances, alternate
diagnostic steps or other diagnostic aids specific to
that chart or circuit.
DIAGNOSTIC CIRCUIT CHECK
The "diagnostic circuit check" verifies the system
is functioning correctly. Some special considerations
to keep in mind while making the "diagnostic circuit
check" are:
Blocking Drive Wheels
The vehicle drive wheels should always be blocked
while checking the system.
t o l d Oxygen Sensor
On some engines, the oxygen sensor will cool off
after only a short period of operation at idle. This will
put the system into "Open Loop." To restore "Closed
Loop" operation, run the engine at part throttle
several minutes and accelerate from idle to part
throttle a few times.
SECTION A - DIAGNOSTIC CHARTS
Component Locations ®@@®@®@©©©©®®©@©®@»®©©®©@@@©®©©©®©©@©®@©®@©®©©©©©©@«@©®@ Page A»-2
ECM Wi ring Diagrams
• • • • • • • • © • • • • • • © • • • © • © © • • • • © • • • • • • • • © © © • • © © • © © • • • © © © • e © ©
Page ^^-3
f
4
ECM Connector Terminal End View © © © © © • • • » Page A-5
Diagnostic Ci rcu it Check
• • • • • • • • • • © • • • • • • © • • • • • • © • © © • © • © © © • © © • • • • © © © © • • • • • • • © o
Page ^k-6
No "Service Engine Soon" Light - Chart A-1 • • •
© © © © o © © © © • • « « • « « • •
Page A-8
No ALDL Data or Won't Flash Code 12 "Service Engine Soon" Light On Steady - Chart A-2 Page A-10
Engine Cranks But Won't Run - Chart A-3 (1 of 2) ©. © »* • • • Page A-12
Fuel System Diagnosis - Chart A-7 (1 of 4) « • © • • » © . • • . • * « • © . © . © . Page A 16
Cold Start Valve Test - Chart A-9
• • • • • • • • • • • • • • • © • • • • • • • • • © • • • • • • • © • © © • • © • • © • • • o ©
Page
A-24
Code 13 Oxygen Sensor Circuit (Open Circuit) © © • . • © © • • • « Page A-26
Code 14 Coolant Temperature Sensor Circuit (High Temperature Indicated) © * Page A-28
Code 15 Coolant Temperature Sensor Circuit (Low Temperature Indicated) . . . . © • . © . . © © © • © Page A-30
Code 21 Throttle Position Sensor (TPS) Circuit (Signal Voltage High) • • • © © © Page A-32
Code 22 Throttle Position Sensor (TPS) Circuit (Signal Voltage Low) ©..©©•©•©© Page A-34
Code 23 Manifold Air Temperature (MAT) Sensor Circuit (Low Temperature Indicated) ©©©©©©© Page A-36
Code 24 Vehicle Speed Sensor (VSS) Circuit « © « • © © • • • Page A-38
Code 25 Manifold Air Temperature (MAT) Sensor Circuit (High Temperature Indicated) Page A-40
Code 32 Exhaust Gas Recirculation (EGR) Circuit « . © Page A-42
Code 33 Manifold Absolute Pressure (MAP) Sensor Circuit (Signal Voltage High - Low Vacuum) . Page A-44
Code 34 Manifold Absolute Pressure (MAP) Sensor Circuit (Signal Voltage Low - High Vacuum) . Page A-46
Cod e 3 5 Idle Speed E rror
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Page ^^-48
Code 42 Electronic Spark Timing (EST) Circuit © © . • © . © . © © . . . © • . Page A-50
Code 44 Oxygen Sensor Circuit (Lean Exhaust Indicated) «• •» • « © « • • © • © © • © • • © Page A-52
Code 45 Oxygen Sensor Circuit (Rich Exhaust Indicated) «© • © ©«©©*•©.©©©© Page A-54
Cod e 51 PROIVl E rror
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Page ^^-56
Code 52 CALPAK Error (Faulty or Missing Calpak) © © ©«• © Page A-56
Code 53 System Over Voltage
• • • • • • • • • • • • • • © • • © • • © • • • • © • © © © • • • • © © © © • • © • • • © • © a © ©
Page A-56
Cod e 5 5 ECfVl E r ror • • • • • • • • • • • • • • • • • • • • © • © • • • • © • © • • • • • • © • © • © • • © • • • © © • © • • © • • © o
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