Workshop Manuals Factory service & repair Fiat
01 General information02 Specifications03 Manufacturing data and tolerances04 Tightening torques05 Fluids and lubricants06 Maintenance07 Diagnostic checks08 Engine09 Clutch10 Gearbox and differential11 Axles and driveshafts12 Brakes13 Steering14 Suspension and wheels15 Heating, air conditioning and auxiliary units16 Electrical equipment17 Body fittings18 Body panels and frame19 Wiring diagrams and electrical functions20 Wiring harnesses21 Connectors and pin-outs22 Fault diagnosis23 Special tools
Fiat 500 Factory Service Manual (2007-2024)22 · Fault diagnosis
22 · Diagnostics

Rear noise (knocking)

Make
Fiat
Model
500 Factory Service Manual
Year
2007–2024
Section
Noise / vibrations › Rear noise (knocking)
Fault diagnosisRear noise (knocking)

REAR NOISE (KNOCKING)

1.2 8v, 1.3 Multijet, 1.4 16v

Whilst driving, especially on unmade roads, there is knocking coming from the rear suspension. This diagnosis can only be made after

See table S015 NOISE WHILST DRIVING

Carry out the latter first.

If the problem is only on one side, carry out the checks and any operations on the appropriate side only.

Test results
0PRELIMINARY CHECKSAll OKProblems encounteredOperation

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 operated

2. The noise is also present in other conditions.

1. Eliminate the handbrake lever and/or actual handbrake clearance

2. Move on to Step 1

1OIL LEAK CHECKAll OKProblems encounteredOperation

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 procedure

2. Replace the shock absorber

Op. 4420A30 REAR SUSPENSION SHOCK ABSORBER (ONE), LEFT OR RIGHT - R.R. - CHECK WHEEL GEOMETRY SEPARATELY

2HANDBRAKE CHECKAll OKProblems encounteredOperation
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 3Inteference 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.
3INTERFERENCE CHECKAll OKProblems encounteredOperation

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 correctly

3. Replace the end of travel buffer

Op. 4420W14 REAR SUSPENSION END BUFFER - REPLACE

4TIGHTENING TORQUE CHECKAll OKProblems encounteredOperation

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 5Torque tightenings not correct.Restore the correct tightening.
4TIGHTENING TORQUE CHECKAll OKProblems encounteredOperation

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 5Torque tightenings not correct.Restore the correct tightening.
5CORRECT OPERATION CHECKAll OKProblems encounteredOperation
Check that the fault is no longer presentEnd of diagnosisThe 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.

Parts & tools for this job For 2007 Fiat 500

Links open Amazon search results in a new tab. As an Amazon Associate I earn from qualifying purchases.