| | Test results |
| 0 | PRELIMINARY CHECKS | All OK | Problems encountered | Operation |
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| Having carried out the road test, during the See table S015 NOISE WHILST DRIVING, there was a knocking noise from the back.Continue depending on the circumstances in which the noise occurs. | End of diagnosis | 1. The noise disappears when the handbrake is operated2. The noise is also present in other conditions. | 1. Eliminate the handbrake lever and/or actual handbrake clearance2. Move on to Step 1 |
| 1 | OIL LEAK CHECK | All OK | Problems encountered | Operation |
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| Raise the vehicle on a two column lift and check that there are no oil leaks from the shock absorber stem. | Slight dampness on the stem is considered normal because there is evaporation during the operation of the shock absorber. |
If there is a persistent oil leak on the shock absorber stem, make sure that it is not coming from other parts of the vehicle that are lubricated | Move on to Step 2 | 1. Leaks from other parts that are lubricated.2. Leaks from the shock absorber stem. | 1. Search for the cause of the leak following the appropriate diagnostic procedure2. Replace the shock absorber Op. 4420A30 REAR SUSPENSION SHOCK ABSORBER (ONE), LEFT OR RIGHT - R.R. - CHECK WHEEL GEOMETRY SEPARATELY |
| 2 | HANDBRAKE CHECK | All OK | Problems encountered | Operation |
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| Check that the handbrake cables or outer casing do not knock against the fuel tank, heat shields or bodywork during oscillations. | Move on to Step 3 | Inteference between outer casing or cables and other elements. | Cover the outer casing with foam rubber tape in the area of the interference or lubricate the cable. |
| 3 | INTERFERENCE CHECK | All OK | Problems encountered | Operation |
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| Check that there are no signs of interference between the suspension elements or between the latter and the bodyshell.In particular, check that there are no signs of wear on the suspension springs and that they do not show signs of abrasion.Check that the end of travel buffer for the rear spring is correctly inserted in its housing in the bodyshell. | If the spring shows signs of abrasion, its mechanical properties could be weakened as a result of oxidation. |
| Move on to Step 4 | 1. Inteference due to incorrect fitting.2. Abrasions or non conformity of the spring.3. End of travel buffer not correctly inserted. | 1. Eliminate the interference and restore the correct fastening. If this is not possible, replace the defective components.2. Replace the spring Op. 4420A48 REAR SUSPENSION COIL SPRINGS - R.R. taking care to fit it correctly3. Replace the end of travel buffer Op. 4420W14 REAR SUSPENSION END BUFFER - REPLACE |
| 4 | TIGHTENING TORQUE CHECK | All OK | Problems encountered | Operation |
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| Locate the area of the possible noise source: top or bottom.Starting from the area where the knocking was identified, check the tightening torques by carrying out the See Test 4420OB CORRECT TIGHTENINGS FOR REAR SUSPENSION CHECKS of the bolts fixing:- Shock absorber upper mounting;
- Shock absorber lower mounting;
- Axle brackets to bodyshell;
- Flexible bush to bracket;
- Stub axle to axle plate;
| Move on to Step 5 | Torque tightenings not correct. | Restore the correct tightening. |
| 4 | TIGHTENING TORQUE CHECK | All OK | Problems encountered | Operation |
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| Locate the area of the possible noise source: top or bottom.Starting from the area where the knocking was identified, check the tightening torques by carrying out the See Test 4420OB CORRECT TIGHTENINGS FOR REAR SUSPENSION CHECKS of the bolts fixing:- Shock absorber upper mounting;
- Shock absorber lower mounting;
- Axle brackets to bodyshell;
- Flexible bush to bracket;
- Brake caliper to wheel hub
| Move on to Step 5 | Torque tightenings not correct. | Restore the correct tightening. |
| 5 | CORRECT OPERATION CHECK | All OK | Problems encountered | Operation |
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| Check that the fault is no longer present | End of diagnosis | The fault persists. | The knocking is caused by another system (e.g. the fuel float in the tank). Carry out the appropriate checks to identify the cause of the noise. |