F 250 4WD LD Pickup V8-281 4.6L VIN W EFI (1997)
Alternative Fuel Control Module: Technical Service Bulletins
Bi-Fuel System - Compuvalve Replacement
Article No.
01-10-6
05/28/01
DRIVEABLITY - BI-FUEL - COMPUVALVE
PRE-REPLACEMENT CHECK LIST - SERVICE TIPS
FORD:
1996-2000 CONTOUR
1994-2001 F-150, F-250 LD
1995-2001 E-250, E-350
1999-2001 SUPER DUTY F SERIES
ISSUE
This article will be used as an aid in diagnosis to avoid unnecessary replacement of the compuvalve on bi-fuel vehicles after normal diagnosis has
determined the compuvalve may be faulty.
ACTION
Complete the normal diagnostic methods and pinpoint tests. Should the conclusion be after normal diagnosis to replace the compuvalve, then follow the
compuvalve Pre-Replacement Checklist (below) before replacing the compuvalve.
SERVICE INFORMATION
Glossary Of Terms
^
ALT - Alternate Fuel Mode
^
FAP - Fuel Absolute Pressure
^
HPS - High Pressure Solenoid
^
VCL - Vehicle Communications Link
^
AFCM - Alternate Fuel Control Module
^
WDS - Worldwide Diagnostic System
^
DTC - Diagnostic Trouble Code
^
MAP - Manifold Absolute Pressure
^
LPG - Liquid Propane Gas
^
EEC - Electronic Engine Control
NOTE
THE FOLLOWING IS A LIST OF KNOWN MIS-DIAGNOSIS OF THE COMPUVALVE REPLACEMENT ON BI-FUEL VEHICLES.
1.
MAP line loose.
2.
High FAP from vaporizer breakdown.
3.
Incorrect interpretation of DTCs.
4.
VCL replacement due to harness faults.
5.
Misfire due to leaking 0-rings.
6.
Compuvalve replaced without checking HPS circuit for correct resistance.
