S10 Engine whistling / unit belt noise
- Make
- Alfa Romeo
- Model
- 147 Factory Service Manual
- Year
- 2000–2002
- Section
- Noise/vibrations › S10 Engine whistling / unit belt noise
S10 Engine whistling / unit belt noise
A high frequency noise is heard from the engine, whose intensity varies with the number of revs
| Step | Test procedure | Result | Action |
|---|---|---|---|
| 0 | PRELIMINARY CHECKS Check the condition of the auxiliary drive belt and check that the tension is correct. See if the whistling stays constant as more electrical loads are conneced. | OK | |
| Belt worn. |
End of diagnosis | ||
| Tension incorrect |
End of diagnosis | ||
| The whistling noise increases. | |||
| 1 | CHECKING ALTERNATOR Check that the alternator is working properly, in particular
| OK | |
| Defective voltage regulator |
End of diagnosis | ||
| Connections not correct |
End of diagnosis | ||
| 2 | CHECKING AUXILIARY DRIVE BELT Check whether the whistling disappears when the belt is disconnected. NOTE: Do not let the engine run for long with the belt disconnected | OK | |
| The whistling disappears: | |||
| The whistling remains constant | |||
| 3 | CHECKING AIR CONDITIONER COMPRESSOR Check the air conditioner air conditioner compressor is working properly. | OK | |
| Air conditioning compressor faulty |
| ||
| 4 | CHECKING BELT TENSION Check the condition of the belt tensioner bearings | OK | |
| Fixed belt tensioner fault |
End of diagnosis | ||
| Mobile belt tensioner fault |
End of diagnosis | ||
| 5 | CHECKING CORRECT OPERATION Check that the fault is no longer present | OK | Incorrect selection of diagnostic procedure |
| Fault persists | Incorrect selection of diagnostic procedure |
Parts & tools for this job For 2000 Alfa Romeo 147
- PARTEngine gasket setSearch: Alfa Romeo 147 2000 engine gasket set
- TOOLTorque wrenchSearch: 3/8 inch torque wrench
- TOOLFeeler gauge setSearch: feeler gauge set
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