FixVault

Symptoms Diagnosis

Symptom checks cannot be used properly unless problem occurs while vehicle is being tested. To reduce diagnostic time, ensure steps in appropriate BASIC TESTING and TESTS W/CODES articles in the ENGINE PERFORMANCE Section were performed before diagnosing a symptom.

Use diagnostic charts to identify systems and components that should be checked for fault. See DIAGNOSTIC CHART INDEX  . Perform check or adjustment procedure indicated in appropriate diagnostic chart.

DIAGNOSTIC CHART INDEX

Driveability Symptom See Chart #
Starting
No Crank 1
Hard Start/Long Crank 2
Stall After Start 3
No Start/Normal Crank 4
Idle
Slow To Return To Idle 5
Rough Idle 6
High Idle 7
Low/Slow Idle 8
Stalls/Quits
At Idle 3
On Acceleration 9
At Cruising Speed 9
On Deceleration 8
Runs Rough
At Idle 6
On Acceleration 10
At Cruising Speed 10
Misses
At Idle 6
On Acceleration 10
At Cruising Speed 10
Buck/Jerk 9
Hesitation
On Acceleration 9
Surge
On Acceleration 9
At Cruising Speed 11
Backfires 12
Lack/Loss Of Power 13
Spark Knock (Pings) 14
Diesels/Runs On 7
Poor Fuel Economy 15
Improper Shift 18
Emissions Compliance 16
Warning Indicators 17
Engine
High Oil Consumption 19
Noise 24
Runs Cold 21
Runs Hot 20
Exhaust Smoke 22
Fuel Odor 23
Vibration 25