Good as the 500 is in many ways, it lacks a basic coating of sound insulation (that benefits the higher specification Pandas) and so is extremely noisy, particularly in diesel form.

Presumably Fiat have done without it to save weight for better emissions, to maximise head room in the rear and perhaps for cost reasons. With the diesel having exactly 110g/km CO2 emissions, clearly weight was critical.

What Can Be Improved

There are four main areas to improve:
  • The doors, which will be covered in a seperate article, which reduces transmission of noise from other vehicles and improves the sound systems bass output (where a sub-woofer is not fitted);
  • The floor pan and fire wall, the subject of this article, which reduces road noise from the front wheels, engine noise and exhaust noise;
  • The roof, which I have not considered since headlining is difficult to remove and very easily damaged, and in any case wind noise is barely audible due to the levels of other noise sources; and
  • The rear section of the car, considered in another article seperately but is logical to do whilst the car is dismantled, including the rear quarters, boot, and under the rear seats.
How Much Difference Will It Make?

The absolute sound level depends on road surface material and state of repair, speed, engine speed, tyres, tyre pressure, temperature, suspension setup, exhaust and more besides. Sound is measured in decibels (dB), and of most interest for this article is dB(A), which measures noise in general except very low frequencies, which any car will always generate a lot of due to the bodywork flexing.

Road noise is dramatically improved on some surfaces and improved to much lesser extent on others due to the variation in the noise components between structure bourne (transmitted through the tyre wall, into the suspension and ultimately into the car through the steelwork directly) and air bourne sound (noise coming from the tyres, and travelling through the air before travelling through the metal work of the car).

On a particular section of road prior to any additional insulation, a measurement of 74dB(A) was attained at 60 mph in top gear. After the procedures in this article and the rear-section article were followed, this reduced to around 67dB(A), a big and very noticable improvement. Some surfaces are now around 64dB(A) whilst old, course grained tarmac is still nudging over 70dB(A) but with a very different tone. In particular, the higher pitched components are massively reduced resulting in much lower volume levels being required on the stereo - comfortable listening is about volume 3 or 4 on the Interscope system.

Tools Required
  • 1/2" drive socket set
  • Allen keys
  • Sharp scissors
A panel removing tool will also assist, but is not absolutely necessary.

Materials Required
  • 12mm felt underlay - around 7 sq.m
  • A few spare Fiat panel clips of each type (grey and blue/green)
  • Non-bitumen based self adhesive sound insulation materials such as Dynamat or Damplifier (around 20 sq.ft)
  • Selection of plasters to cover various nuckle skinnings
Materials such as Dynamat are applied to sheet metals to reduce viabration in the panels. Although thin, they are effective in reducing transmission of low frequency sounds (mostly below around 200Hz). Thicker layers of dense, soft materials are required to absorb higher frequency sounds that make up the majority of road noise. A combination will provide the best reduction.

Bitumen based self adhesive pads or not recommended since they degrade and can become detached or melted at temperatures attainable within a car sitting in hot sun. They also have an odour, particularly when warm.




Removal of Boot Trimmings

See article on rear section.

Removal of Rear Seats

See article on rear section.

Removal of Door Sills

Remove the two screws, one at each end, and the strip can then be pulled upwards, working along the length, using a trim removal tool to assist where necessary to overcome the plastic clips:

Removal of Plastic Trim Panels

See article on rear section.

Note that the rear quarter pannels cannot be completely removed without special tools or buy cutting the panel because the front seat belt is mounted through it. However there is sufficient play to allow the pannel to be moved around as required for the remainder of the procedure once unclipped from the car.

Removal of Front Seats

The front seats are secured by four black allen bolts and a fifth brass coloured allen bolt that is used to align the track. Removal is straightforward and takes no more than a few minutes. Ensure the battery negative terminal has been disconnected for at least 30 minutes before proceeding.
  • Loosen the brass coloured allen bolt a couple of turns on the outer rear of the seat:
  • Disconnect the wiring harnesses and pop out the retaining plug:
  • Work the wires into a position where they will not be caught when removing the seat.
  • If the Interscope sub woofer is fitted, disconnect it's wiring plug and move the cable clear.
  • Slide the seat forward and remove the two rear black bolts. Note that the inner rear bolt is screwed into a moving bolt - this is mounted within the chasis and presumably won't drop inside. However, be careful not to move it too far just in case, and once the seat is out, reinsert the bolt to hold it in place.
  • Slide the seat back just enough to expose the two front bolts and remove these.
  • The seat can now be lifted clear, lifting out with the base leading and taking care not to scuff the door trim with the rails.

Removal of Central Tunnel Trim

The trim around the handbrake encorporating the cup holders is secured by three bolts hidden under the cup holder non-slip pads and another bolt in between the two sections. The trim around the base of the center console encorporating the foot level air vents must also be removed. Contrary to the workshop manul, removal of the gear knob is not neccessary provided that at least one seat has been removed.
  • Starting on the passenger side, remove the screw near the lower vent, pull the pannel off, and remove the screw under it (note these have torx heads):
  • Moving to the drivers side, remove the two allen bolts in the foot rest section and the screw near the vent, pull the pannel off and remove the screw under it (again a torx head):
  • Lift the cup holder non-slip bases and remove the nuts below them:
  • Pull the rear most section directly back and remove. Take care not to loose the small cap under the handbrake handle which will drop out:
  • Remove the bolt that is exposed and pull the front section clear gently since the electrical outlet and USB cables are secured to the underside:
  • Remove the electrical connections. The USB plug is removed but rotating the blue 'handle' about 90 degrees:
  • Pull out the two sponge pieces under the ventilation system.

Removal of Interscope Subwoofer (where fitted)

The speaker is secured by three bolts. These are simply removed, the wiring plug disconnected, and the unit lifted out:


Removal of the Carpet

The complete carpet can now be removed. Since the carpet was originally fitted before the dashboard, a few small cuts are required, all best accomplished from the passenger side:
  • under the dash, the the very front most section (this is best accomplished from the passenger side);
  • under the dash, under the ventilation outlets; and
  • the thin strip in front of the handbrake.
These will be totally covered once the trims are refitted. Use a sharp Stanley knife, taking extreme care to avoid any cables under the carpet.

A throttle stop must also be removed, this simply unscrews, and where air conditioning is fitted, the condensate drain tube must be disconnected from the base of the evaporator (near the foot rest on the drivers side):


The carpet can now be lifted clear, taking care to avoid snagging the remaining centre sections.

The carpet features some fairly thick fiberous sound insulation under about half of its area, helping to level the floor pan.

Adding Dynamat or Damplifier Damping Material

Once the carpet has been removed, the bare metal floor pan is mostly exposed except for the heavy matting fitted to the firewall under the dashboard, which cannot be removed without first removing the dash board itself.

Much of this metal work is quite thin and will be carrying structure-bourne noise directly into the car, particularly engine and exhaust noise. A covering with specialist matting such as Damplifier will reduce this noise transmission, but it time consuming. Around 20 sq.ft will be required.

Dust off the metal and heat gently if the outside temperature is below around 18*C. Work the matting over the majority of the area, taking care to avoid skin damage on the sharp foil edges - gloves are advisable. Make sure the pads are fully in contact with the metal.

Cover the floor panel, the raised sections, the exhaust tunnel and the section running vertically up where the rear seat bolts are positioned.

Removing wiring mounts as you work and cover all holes but cut the mat to re-expose the wiring mount holes and seat mounting points. Allow at least two hours for this stage.


Adding Felt Insulation

There is sufficient give in the fittinngs to accomodate a 12mm thick layer of felt insulation - just. An 8mm layer would be easier to work with and to accomodate, but would obviously provide less insulating effect.

Make sure all tools are removed from the floor area before proceeding!!

Disconnect the hand brake sensor as it's easy to catch and could be damaged.

The felt can be installed in four sections. Cut the approximate overall size by laying the carpet on top and cutting around, allowing a good space all the way aroung. Next, divide down the middle and then cut a length to fit the rear section - the remaining will fit the front. Don't cut it too short.

Because of the contours of the floor pan, many cuts are required to allow it to sit within the shape of its own accord. No glue is necessary and the carpet will hold it firmly in position.

The felt should be cut around the wiring clips and tucked under the wiring are the outer edges and run up the firewall to about as high as the carpet runs. Leave the two handbrake cables clear since these are greased and could become clogged with fibres.


If the Interscope subwoofer is fitted, leave the drivers side cross member clear of felt since there is insufficient clearance under the sub woofer.

Leave the area in front of the seatbelt pretensioners clear.

Reconnect the handbrake sensor cable.

Refitting the Carpet

Make sure all tools are removed before proceeding!!

If the Interscope sub woofer is fitted, test fit the sub woofer to align and securely tighten it's mounting brackets. Remove and set aisde.

The carpet can then be laid directly over the newly added felt underlay. Care is required to ensure the felt down not 'ruck up' when fitting.


Since the carpet is contoured for fittment without the felt, some 'working in' will be required in places. Remove any excess felt that is clearly going to cause a problem.

Reconnect the air conditioning condensate drain, if fitted, and pull the various wiring connectors back through.

Additional Areas to Insulate or Dampen

Since writing the rear section article, two additional areas that can be insulated or dampened have been identified.

The rear quarter pannels can benefit from a layer of Damplifier on the centre section:


An additional layer of 8mm felt could also be added to the back of the panel, mounted around the clips.

The rear trim panels through which the rear seat belts are fed can accomodate a 12mm layer of felt:


Refitting Procedure

Start with the rear quarters and the side sills. These will be a pretty tight fit, requiring some working into position and possible a little trimming of the felt under the carpet near the seat belt pretensioners. However the clips are strong and the rear quarters are held securely by the door seals, the seats, and three screws.

The drivers side sill can accomodate some felt insulation inside the footwell.

Next refit the central tunnel trim (refit the two sponges first). The bolts are extremely tight over the insulation, it may be preferable to either machine some custom bolts or cut back some insulation to allow for greater compression.

Refit the ventilation covers in the foot well, these should go on more easily with a little persuading.

Refit the sub-woofer, if fitted. It cannot be forced down over insulation - any left over the cross member must be removed immediately under it. The Damplifier is however OK.

Refit the seats, ensuring the bolts are turned in by hand to prevent misthreading. When lifting the seats in, they can be dropped straight on to the brass leveling screw that remains. Trim any excess insulation through the carpet holes using wire clippers, taking great care to avoid any wires.

Reconnect the wiring harnesses and refit the securing clips.

The remainer of the car is reassembled as per the rear section guide.

Reconnection of the Battery


When connected, nothing will happen and the remote will not respond. Leave the car for around a minute, and then turn the ignition (but do not start). At this point the car will come to life and work the fuel pump etc in the usual way. The date and time and trip A/B are lost but all other settings are retained. The remote will now function again.