Chevrolet 1963 Corvette, Руководство по ремонту и настройке

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174 EMISSION CONTROLS AND FUEL SYSTEM
Fuel injection system diagram
time, check for throttle shaft binding. If such
a condition exists, attempt to remedy by
soaking in solvent. If the throttle shaft still
binds, disconnect the throttle shaft from the
linkage, remove the throttle plate screws, and
file the burrs on the shaft. Remove the shaft,
clean, rebush and then reassemble. During
reassembly, preset the idle-speed and idle-
fuel adjusting screws
IVz turns out from the
bottom.
17. Fuel meter reassembly is the reversal
of the disassembly procedure. When install-
ing the main control diaphragm, keep in mind
that the slots in the diaphragm should readily
align with the cover attaching screw holes lo-
cated in the bowl cover. Repeat the reassem-
bly steps until the diaphragm holes line up
naturally. Do not force this alignment. If the
diaphragm seemed tight when removed, it is
defective. The replacement diaphragm should
not be installed in the same condition. At this
time check the clearance between the hous-
ing and the enrichment diaphragm. A mini-
mum of 0.040 in. is required to prevent in-
terference during power stop operation.
Adjust the diaphragm shaft length to gain
proper clearance.
Check the fuel reservoir float settings be-
fore replacing the top cover. Float level
should be 2
9
/32 in. while float drop should be
2
27
/32 in. Bend to adjust.
Twin Throttle Body Injection
(TBI) System (Marketed as
Cross-Fire Injection®)
The TBI system, introduced as standard
equipment on the 1982 Corvette, is a com-
pletely electronic system which meters and
delivers precise amounts of fuel and air to the
engine, according to the exact engine oper-
ating requirements at any given time. The
system is controlled by the same on-board
computer (ECM) used with the emissions
system (CCC). Through the monitoring of
various sensors, the ECM determines the
optimum air/fuel ratio and signals the TBI
units to adjust the ratio accordingly. TBI is
designed to offer the owner trouble-free
starting, immediate throttle response, and
maximum fuel efficiency; regardless of
weather conditions, engine rpm, tempera-
ture or load.
Trouble diagnosis of the injection system is
nearly impossible for the novice mechanic to
perform, because of the interaction between
the injection, emissions, and ignition sys-
tems; all of which are controlled by the ECM.
Should you encounter any type of engine
performance problem, have a complete CCC
system test performed by a qualified, profes-
sional technician. If the fault lies in the injec-
tion system, you can use the following pro-
NORMAL FUEL LEVEL
FUEL INLET \ CONTROL DIAPHRAGM ENRICHMENT
TOWER/LEVER
ELEC. SWITCH IDLE MIXTURE SCREW VENTURI SIGNAL
EXHAUST STOVE
COLD
ENRICHMENT
HOUSING
THERMOSTAT