Choke Housing-Disassembled; Accelerator Pump - Pontiac TRANS AM 1977 Service Manual

FUEL SYSTEM
ATTACHING SCREWS
A
JSHlNC
P
SPRING
WASHER
-RETURN SPRING
VP
-DIAPHRAGM AND SHAFT
FAST IDLE
LEVER
1
SPRING
I
CHOKE
RETAINER LEVER
O-RING
FAST
\
LOCKWASHER
\
LINK RETAINER
1140 ONLY) COl L
SHAFl
Fig. 6C-3 1 Choke Housing
-
Disassembled
Fig. 6C-32 Accelerator Pump
B. Hesitation
2. Inspect pump return spring for being weak or
distorted.
3. Check all pump passages and jets for dirt and
improper seating inlet or discharge balls.
4. Check pump linkage for excessive wear, repair or
replace as necessary.
C. Hard Starting
-
Poor Cold Operation
1. Check choke valve and linkage for excessive wear,
binds or distortion.
2. Inspect choke vacuum diaphragms for leaks.
3. Clean or replace carburetor filter.
4. Inspect inlet needle and seat assembly for sticking,
dirt, etc.
5. Examine fast idle cam for wear or damage.
6. Also check items under "flooding".
D. Poor Performance
-
Poor Gas Mileage
1. Check power piston and power valve for dirt, sticking,
binding, damaged parts or excessive wear.
2. Clean all fuel and vacuum passages in castings.
E. Rough Idle
1. Inspect idle needle for ridges, burrs or being bent.
2. Inspect gasket mating surfaces on castings for damage
to sealing beads, nicks and burrs.
3. Clean all idle fuel passages.
4. Check throttle lever and valves for binds, nicks and
other damage.
1. Inspect pump diaphragm for cracks, scores or
excessive wear.