Pontiac FIREBIRD 1972 Service Manual page 655

SECTION 66
ENGINE FUEL
CONTENTS OF THIS SECTION
Fuel-General Trouble Diagnosis and Testing
........
6B- 1
Carburetor Air Cleaner and Silencer
......................
6B-3
Heat Control Valve
..................................................
6B-3
Intake Systems-Ram Air
........................................
6B-4
Idle Stop Solenoid
................................................
6B-5
Accelerator Linkage and Adjustment
....................
6B-5
Hot Idle Compensator
............................................
6B-5
Fuel Pump
..............................................................
6B-6
Trouble Diagnosis and Testing
..........................
6B-7
Description
.........................................................
6B-6
MV Monojet Carburetor
......................................
6B- 10
Trouble Diagnosis
..............................................
6B- 1 1
General Description
..........................................
6B- 13
Operating Systems
..............................................
6B- 14
Carburetor Usage Chart
........................
. .
.......
6B- 18
Overhaul and Adjustment
................................
6B- 19
WG
D
Carburetor
..................................................
6B-29
Description and Operation of Auto. Choke
....
6B-30
Adjustment of Fast Idle Cam, Choke
Disassembly, Cleaning and Inspection
..............
6B-32
Assembly and Adjustment
................................
6B-34
2GV Carburetor
....................................................
6B-36
Trouble Diagnosis
..............................................
6B-37
General Description
.........................................
6B-38
Operating Systems
..............................................
6B-40
Carburetor Usage Chart
....................................
6B-44
Adjustments on Car
..........................................
6B-44
Periodic Service
..................................................
6B-44
Overhaul and Adjustment
................................
6B-44
4MV Quadrajet Carburetor
..................................
6B-55
Trouble Diagnosis
..............................................
6B-56
General Description
..........................................
6B-58
Operating Systems
..............................................
6B-59
Carburetor Usage Chart
.................................
6B-68
.........................................
Adjustments on Car 6B-68
Periodic Service
................................................
6B-68
Overhaul and Adjustment
................................
6B-68
Carburetor Service Specifications
..........................
6B-82
Unloader and Fast Idle Tang
........................
6B-31
GENERAL TROUBLE DIAGNOSIS AND TESTING
All Pontiac engines have been designed to operate effi-
ciently and with lower exhaust emissions on low lead or
no lead gasolines. If low lead or no lead gasoline is not
available, any leaded regular grade gasoline with a Re-
search Octane Number of 91 or higher may be used.
When carburetor troubles are encountered they can usu-
ally be corrected by making the adjustments outlined un-
der ADJUSTMENTS ON CAR.
NOTE: Before any work is performed on the
carburetor, make sure trouble is not due to poor
compression, or fault o f ignition system due to
improper timing, defective spark plugs, burned
ignition points, etc.
POOR FUEL ECONOMY
NOTE: Before any attempt is made to improve
fuel economy, the actual gasoline mileage
should be determined, using a tenth of a gallon
tester. I f mileage obtained during this test com-
pares favorably with that found on other nor-
mal cars, the poor mileage must be attributed
to driving conditions or driving habits of the
owner. Also consider factors such as dragging
brakes, soft tires, improper tire size and im-
proper speedometer driven gear.
Fig. 6B-1 Air Cleaner Installation (6 Cyl.)