Voyager L4-135 2.2L SOHC (1985)
Technical Service Bulletin # 181385A
Date: 850826
Fuel System - Vapor Lock/ Fuel Foaming
Models
1984-1985 Caravan Ram Van & Voyager Vehicles Equipped With 2.2L Carbureted Engine
Subject
Vapor Lock/ Fuel Foaming
Index
DRIVEABILITY
Date
August 26, 1985
No.
18-13-85 REVISION A
This bulletin supersedes Technical Service Bulletin #14-48-84 for subject vehicles equipped with 2.2L engine and also #18-13-85, which should be
removed from your files.
A diode wiring jumper, PN 4331924, has been added to the vapor lock/fuel foaming parts package. This bulletin includes installation instructions for the
additional wiring jumper.
Symptom/Condition, Diagnosis & Parts Information
SYMPTOM/CONDITION
Vapor Lock - Engine performance is gradually reduced in high ambient temperature or high altitude driving due to a drop in fuel pressure, which starves
the engine for fuel (goes lean). Engine may not start until fuel system components cool off.
Fuel Foaming - Engine sags and/or exhibits poor performance following a hot soak restart. This condition occurs when cool incoming fuel meets the hot
fuel in the carburetor fuel bowl, which creates an over rich condition. Engine will start (unloading technique may be necessary).
DIAGNOSIS
Vapor lock and fuel foaming cause similar conditions. The following are characteristics of each condition and should be observed on a fully warmed up
engine. (These conditions do not affect cold engine driveability.)
Vapor Lock
^
Occurs after hot soak, prolonged idle, or highway speeds at any throttle opening.
^
Sag due to lean mixture.
^
No black smoke at tailpipe.
^
Fuel pressure drops to 0.
^
Carburetor air horn dry.
^
No accelerator pump discharge.
^
May not start until engine. cools.
^
Engine may not sustain heavy loads.
Revised part numbers, TSB 18-37-85, pages 2, 4, 7, and 8, December 8, 1986
Fuel Foaming
^
Occurs primarily after hot soak restart or prolonged idle only on medium to heavy acceleration.
^
Sag due to rich fuel mixture.
^
Black smoke at tailpipe.
^
Fuel pressure is normal.
^
Raw fuel at carburetor air horn.
^
Good accelerator pump discharge.
^
Will start immediately (unloading technique may be necessary).
