#
ENGINE SYMPTOM TROUBLESHOOTING

id010300800300
• Confirm trouble symptom using the following diagnostic index, then go to appropriate troubleshooting chart.

Diagnostic Index

No. | TROUBLESHOOTING ITEM | DESCRIPTION
--- | --- | ---
1 | Melting of main or other fuses | -
2 | MIL illuminates | The MIL is illuminated incorrectly.
3 | Will not crank | The starter does not work.
4 | Hard to start/long crank/erratic start/erratic crank | The starter cranks the engine at normal speed but the engine requires excessive cranking time before starting.
5 | Engine stalls. | After start/at idle | The engine stops unexpectedly at idle and/or after start.
6 | Cranks normally but will not start | The starter cranks the engine at normal speed but the engine will not run.
7 | Slow return to idle | The engine takes more time than normal to return to idle speed.
8 | Engine runs rough/rolling idle | The engine speed fluctuates between specified idle speed and lower speed and the engine shakes excessively.
9 | Fast idle/runs on | The engine speed continues at fast idle after warm-up. The engine runs after the ignition switch is turned to off.
10 | Low idle/stalls during deceleration | The engine stops unexpectedly at beginning of deceleration or recovery from deceleration.
11 | Engine stalls/quits. | Acceleration/cruise | The engine stops unexpectedly at beginning of acceleration or during acceleration. The engine stops unexpectedly while cruising.
Engine runs rough. | Acceleration/cruise | The engine speed fluctuates during acceleration or cruising.
Misses | Acceleration/cruise | The engine misses during acceleration or cruising.
Buck/jerk | Acceleration/cruise/ deceleration | The vehicle bucks/jerks during acceleration, cruising, or deceleration.
Hesitation/stumble | Acceleration | Momentary pause at beginning of acceleration or during acceleration
Surges | Acceleration/cruise | Momentary minor irregularity in engine output
12 | Lack/loss of power | Acceleration/cruise | Performance is poor under load. (e.g., power down when climbing hills)
13 | Knocking/pinging | Acceleration/cruise | Sound is produced when air/fuel mixture is ignited by something other than spark plug. (e.g., hot spot in combustion chamber)
14 | Poor fuel economy | Fuel economy is unsatisfactory.
15 | Emission compliance | Fails emissions test.
16 | High oil consumption/leakage | Oil consumption is excessive.
17 | Cooling system concerns | Overheating | The engine runs at higher than normal temperature/overheats.
18 | Cooling system concerns | Runs cold | The engine does not reach normal operating temperature.
19 | Exhaust smoke | Blue, black, or white smoke from exhaust system
20 | Fuel odor (in engine compartment) | Gasoline fuel smell or visible leakage
21 | Engine noise | Engine noise from under hood
22 | Vibration concerns (engine) | Vibration from under hood or driveline
23 | A/C does not work sufficiently. | The A/C compressor magnetic clutch does not engage when the A/C is turned on.
24 | A/C is always on or A/C compressor runs continuously. | The A/C compressor magnetic clutch does not disengage.
25 | A/C is not cut off under WOT conditions. | The A/C compressor magnetic clutch does not disengage under WOT.
26 | Exhaust sulphur smell | Rotten egg smell (sulphur) from exhaust
27 | Spark plug condition | Incorrect spark plug condition
28 | ATX concerns | Upshift/downshift/ engagement | ATX concerns not related to engine performance