SYMPTOM DIAGNOSTIC INDEX [MZI-3.7]

id0103d2800500

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

Diagnostic Index

No. | TROUBLESHOOTING ITEM | DESCRIPTION | PAGE
--- | --- | --- | ---
1 | Melting of main or other fuses | — | (See NO.1 MELTING OF MAIN OR OTHER FUSES [MZI-3.7].)
2 | MIL illuminates | • MIL is illuminated incorrectly. | (See NO.2 MIL ILLUMINATES [MZI-3.7].)
3 | Will not crank | • Starter does not work. | (See NO.3 WILL NOT CRANK [MZI-3.7].)
4 | Hard to start/long crank/erratic start/erratic crank | • Starter cranks engine at normal speed but engine requires excessive cranking time before starting. | (See NO.4 HARD TO START/LONG CRANK/ERRATIC START/ERRATIC CRANK [MZI-3.7].)
5 | Engine stalls | After start/at idle | • Engine stops unexpectedly. | (See NO.5 ENGINE STALLS-AFTER START/AT IDLE [MZI-3.7].)
6 | Cranks normally but will not start | • Starter cranks engine at normal speed but engine will not run. | (See NO.6 CRANKS NORMALLY BUT WILL NOT START [MZI-3.7].)
7 | Slow return to idle | • Engine takes more time than normal to return to idle speed. | (See NO.7 SLOW RETURN TO IDLE [MZI-3.7].)
8 | Engine runs rough/rolling idle | • Engine speed fluctuates between specified idle speed and lower speed and engine shakes excessively. • Idle speed is too slow and engine shakes excessively. | (See NO.8 ENGINE RUNS ROUGH/ROLLING IDLE [MZI-3.7].)
9 | Fast idle/runs on | • Engine speed continues at fast idle after warm-up. • Engine runs after ignition switch is turned to off position. | (See NO.9 FAST IDLE/RUNS ON [MZI-3.7].)
10 | Low idle/stalls during deceleration | • Engine stops unexpectedly at beginning of deceleration or recovery from deceleration. | (See NO.10 LOW IDLE/STALLS DURING DECELERATION [MZI-3.7].)
11 | Engine stalls/quits | Acceleration/cruise | • Engine stops unexpectedly at beginning of acceleration or during acceleration. • Engine stops unexpectedly while cruising. | (See NO.11 ENGINE STALLS/QUITS, ENGINE RUNS ROUGH, MISSES, BUCK/JERK, HESITATION/STUMBLE, SURGES [MZI-3.7].)
Engine runs rough | Acceleration/cruise | • Engine speed fluctuates during acceleration or cruising.
Misses | Acceleration/cruise | • Engine misses during acceleration or cruising.
Buck/jerk | Acceleration/cruise/ deceleration | • Vehicle bucks/jerks during acceleration, cruising, or deceleration.
Hesitation/stumble | Acceleration | • Momentary pause at beginning of acceleration or during acceleration.
Surges | Acceleration/cruise | • Momentary pause at beginning of acceleration or during acceleration.
12 | Lack/loss of power | Acceleration/cruise | • Performance is poor under load (such as power down when climbing hills). | (See NO.12 LACK/LOSS OF POWER-ACCELERATION/CRUISE [MZI-3.7].)
13 | Knocking/pinging | Acceleration/cruise | • Sound is heard when air/fuel mixture is ignited by something other than spark plug (such as hot spot in combustion chamber). | (See NO.13 KNOCKING/PINGING-ACCELERATION/CRUISE [MZI-3.7].)
14 | Poor fuel economy | • Fuel economy is unsatisfactory. | (See NO.14 POOR FUEL ECONOMY [MZI-3.7].)
15 | Emission compliance | • Fails emissions test. | (See NO.15 EMISSION COMPLIANCE [MZI-3.7].)
16 | High oil consumption/leakage | • Oil consumption is excessive. | (See NO.16 HIGH OIL CONSUMPTION/LEAKAGE [MZI-3.7].)
17 | Cooling system concerns | Overheating | • Engine runs at higher than normal temperature/overheats. | (See NO.17 COOLING SYSTEM CONCERNS-OVERHEATING [MZI-3.7].)
18 | Cooling system concerns | Runs cold | • Engine takes excessive time to reach normal operating temperature. | (See NO.18 COOLING SYSTEM CONCERNS-RUNS COLD [MZI-3.7].)
19 | Exhaust smoke | • Blue, black, or white smoke from exhaust system. | (See NO.19 EXHAUST SMOKE [MZI-3.7].)
20 | Fuel odor (in engine compartment) | • Gasoline fuel smell or visible leakage. | (See NO.20 FUEL ODOR (IN ENGINE COMPARTMENT) [MZI-3.7].)
21 | Engine noise | • Engine noise from under bonnet. | (See NO.21 ENGINE NOISE [MZI-3.7].)
22 | Vibration concerns (engine) | • Vibration from under bonnet or driveline. | (See NO.22 VIBRATION CONCERNS (ENGINE) [MZI-3.7].)
23 | A/C does not work sufficiently | • A/C compressor magnetic clutch does not engage when A/C is turned on. | (See NO.23 A/C DOES NOT WORK SUFFICIENTLY [MZI-3.7].)
24 | A/C is always on or A/C compressor runs continuously | • A/C compressor magnetic clutch does not disengage. | (See NO.24 A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY [MZI-3.7].)
25 | A/C does not cut off under wide open throttle conditions | • A/C compressor magnetic clutch does not disengage under WOT. | (See NO.25 A/C DOES NOT CUT OFF UNDER WIDE OPEN THROTTLE CONDITIONS [MZI-3.7].)
26 | Exhaust sulphur smell | • Rotten egg smell (sulphur) from exhaust. | (See NO.26 EXHAUST SULPHUR SMELL [MZI-3.7].)
27 | Fuel refill concerns | • Fuel tank is not filled smoothly. | (See NO.27 FUEL REFILL CONCERNS [MZI-3.7].)
28 | Fuel filling shut off concerns | • Fuel does not shut off properly. | (See NO.28 FUEL FILLING SHUT OFF CONCERNS [MZI-3.7].)
29 | Spark plug condition | • Incorrect spark plug condition. | (See NO.29 SPARK PLUG CONDITION [MZI-3.7].)
30 | ATX concerns | Upshift/downshift engagement | • ATX concerns not related to engine performance. | (See SYMPTOM TROUBLESHOOTING ITEM TABLE [AY6A-EL, AY6AX-EL].)