NO. 21 ENGINE NOISE [MZI-3.7]
| 21 | ENGINE NOISE |
|---|---|
| DESCRIPTION | Engine noise from under hood |
| POSSIBLE CAUSE | Squeal, click or chirp noise: Improper engine oil level Improper drive belt tension Auto tensioner bearing malfunction Improper installation of purge solenoid valve Generator installation (alignment) Splash shield or under cover looseness (splashed water to drive belts) Rattle sound noise: Loose parts Hiss sound noise: Vacuum leakage Loose spark plug Air leakage from intake-air system Rumble or grind noise: Improper drive belt tension Improper P/S fluid level Rap or roar noise: Dynamic dumper looseness Exhaust system looseness Intake-air system looseness Variable valve timing actuator malfunction Other noise: Camshaft friction gear noise or tappet noise Timing chain noise |
NO. 21 ENGINE NOISE REFERENCE CHART (MZI-3.7)
NO. 22 VIBRATION CONCERNS (ENGINE) [MZI-3.7]
| 22 | VIBRATION CONCERNS (ENGINE) |
|---|---|
| DESCRIPTION | Vibration from under hood or driveline |
| POSSIBLE CAUSE | Loose attaching bolts or worn parts Cooling fan Drive belt and pulleys Generator Engine mounts Exhaust mounts Components malfunction such as worn parts Improper balance of wheels and tires Driveline malfunction Suspension malfunction |
NO. 22 VIBRATION CONCERNS (ENGINE) REFERENCE CHART (MZI-3.7)
Vibration Method
- If malfunction occurs or becomes worse while driving on a rough road or when the engine is vibrating, perform the steps below. NOTE: There are several reasons vehicle or engine vibration could cause an electrical malfunction. Inspect the following: Connectors not fully seated Wiring harnesses not having full play Wiring harnesses laying across brackets or moving parts Wiring harnesses routed too close to hot parts An improperly routed, improperly clamped, or loose wiring harness can cause wiring to become pinched between parts. The connector joints, points of vibration, and places where wiring harnesses pass such as through the firewall and body panels are the major areas to be checked.
Scheme 19
- Connect the M-MDS to the DLC-2.
- Turn the ignition switch to the ON position (Engine off). NOTE: If the engine starts and runs, perform the following steps during idle.
- Access PIDs for the switch you are inspecting.
- Turn the switch on manually.
- Slightly shake each connector or wiring harness vertically and horizontally while monitoring the PID. If PID value is unstable, inspect for poor connection.
Scheme 20
- Connect the M-MDS to the DLC-2.
- Turn the ignition switch to the ON position (Engine off). NOTE: If the engine starts and runs, perform the following steps during idle.
- Access PIDs for the switch you are inspecting.
- Slightly shake each connector or wiring harness vertically and horizontally while monitoring the PID. If PID value is unstable, inspect for poor connection.