Fuel Injection - Misfire Diagnostics: Overview

03/21/97

19/02/97/NAS

SUBJECT
PRIDE - Fuel Injector Misfire Diagnostics

MODEL
Range Rover 4.0/4.6

Discovery
Defender

AFFECTED VEHICLES
LP 1995-1997
LH
LJ 1996-1997
LD 1997

DETAIL





If the diagnosis of a misfire fault has been unsuccessful using the tests outlined in Pride Phases 1 and 2 (TIB 12/03/96/US), it will be necessary to confirm that the fuel injectors are functioning properly. The GEMS fuel injection diagnostics check the injector circuits for continuity or short circuits but will not determine whether an injector is mechanically blocked or restricted.

NOTE:
This TIB is for GEMS equipped vehicles. These test may be used on non-GEMS systems also.

The diagnostic steps and repair procedures detailed on the following pages were developed as an element of the Land Rover Way Operation PRIDE. This TIB provides a library location for PRIDE information within the Land Rover North America technical literature system.

ACTION REQUIRED

When misfire symptoms are unresolved, perform injector diagnosis as outlined below.

PARTS INFORMATION

Required Tools

Kent-Moore supplied tools:
^ LR3398 - Fuel Injector Balance Tester
^ LR7211 - Fuel Pressure Gauge
^ LR7272 - Fuel Pressure Gauge Adapter
Snap-on(R) - P.A.C.

PROCEDURE

TestBook

1. Hook up TestBook and follow directions to retrieve fault codes.
2. Complete a DTCR along with freeze frame data and FAX to LRNA.
3. Follow basic diagnostic directions as specified by TestBook.
4. If TestBook tests do not resolve the problem follow the procedure below.





NOTE:
A very high percentage of misfire problems will be found by following the procedures outlined in TIB 12/03/96/US. Do not undertake this injector test unless you have accurately followed the diagnostic procedures outline in Operation PRIDE Phase I and Phase II (TIB 12/03/96/US).

WARRANTY

Normal warranty procedures and policies apply

COMP. CODE

7G8

SRO

18.90.89.27 - Time: 0.60 hr.
Fuel Injector Balance Test