Engine Diagnosis - Isuzu 1999 RODEO Workshop Manual

Engine Diagnosis

Hard Starting
1. Starting Motor Does Not Turn Over
Trouble Shooting Procedure
Turn on headlights and starter switch.
Condition
Headlights go out
considerably considerably
2. Ignition Trouble — Starting Motor Turns Over But Engine Does Not Start
Spark Test
Disconnect a high tension cable from any spark plug.
Connect the spark plug tester J–26792 (ST–125), crank
the engine, and check if a spark is generated in the spark
plug tester. Before cranking the engine, make sure that
the spark plug tester is properly grounded. To avoid elec-
trical shock, do not touch the high tension cable while the
engine is running.
Condition
Spark jumps across gap
No sparking takes place
Possible cause
or dim Battery run down or under charged
Terminals poorly connected
Starting motor coil circuit shorted
Starting motor defective
Possible cause
Spark plug defective
Ignition timing incorrect
Fuel not reaching fuel injector(s) or
engine
Valve timing incorrect
Engine lacks compression
Ignition coil disconnected or broken
Electronic Ignition
module
Poor connections in engine harness
Powertrain Control Module cable
disconnected or defective
ENGINE MECHANICAL (X22SE 2.2L)
Recharge or replace battery
Clean battery posts and terminals
and connect properly
Overhaul or replace
Overhaul or replace
Clean, adjust spark gap or replace
Refer to Ignition System
Refer to item 3 (Trouble in fuel
system)
Adjust
Refer to item 4 (Engine lacks
compression)
Connect properly or replace
System with Replace
Correct
Correct or replace
6A–3
Correction
Correction