Fuel System - Engine Sags/Poor Performance
88chrysler11Models
All "NF45Z" (Vista)
1985-1987 4-Wheel Drive
1986-1987 2-Wheel Drive
Subject
Fuel Foaming Correction
Index
DRIVEABILITY
Date
September 6, 1988
No.
P-3669 18-02-88 REVISION A
(C18-17)
This bulletin supersedes Technical Service Bulletin # 180288, dated 1/18/87, which should be removed from your files. This bulletin has been revised to include California emissions.
SYMPTOM/CONDITION
Engine sags and/or exhibits poor performance following a hot soak restart. The condition occurs when cool incoming fuel meets the hot fuel in the carburetor fuel bowl. The cool fuel evaporates and expands inside the fuel bowl, which creates an over rich condition.
DIAGNOSIS
Engine must be fully warmed up (fuel foaming does not affect cold engine driveability).
^ Occurs primarily after hot soak restart or prolonged idle.
^ Only on medium to heavy acceleration.
^ Sag is due to rich fuel mixture.
^ Black smoke at tailpipe.
^ Fuel pressure is normal.
^ Raw fuel at carburetor air horn.
^ Good accelerator pump discharge.
^ Will immediately start (unloading technique may be necessary).
PARTS REQUIRED
Modified carburetor/gasket package ordered separately by application.
Model Year
1986-1987 2 WD With Manual Transmission PN MD997498
1986-1987 2 WD With Manual Transmission PN MD997526
With California Emissions
Model Year
1986-1987 2 WD With Automatic Transmission PN MD997499
1986-1987 2 WD With Automatic Transmission PN MD997527
With California Emissions
1985-1987 4 WD With Manual Transmission PN MD997500
1985-1987 4 WD With Manual Transmission PN MD997528
With California Emissions
REPAIR PROCEDURE
This repair involves replacing the vehicle carburetor.
1. Remove carburetor per service manual procedure and install new carburetor with the supplied base gasket.
FIGURE 1:
2. Type information on the Authorized Modification Label, PN 4275086, as shown in Figure 1 and attach near VECI label (on the inside of the hood in the engine compartment).
POLICY: Information only