The interiors of cars are often subject to as much abuse as the exterior surfaces, yet are often neglected when it comes to detailing. It wasn't long ago that the state of the nation's car interiors made the news - apparently a very high percentage harbour levels of dirt and bacteria that are potentially unsafe to human health! If you stop and think about this, it is not really that surprising. Most car interiors are only cleaned once or twice a year, and the rest of the time dirt and grime are dragged in from the street, sticky messes are deposited by children (we know all about this one), bacteria are brought in by pets and all manner of other biological nasties are deposited by way of sweating, coughing, sneezing, vomiting, or worse.
In addition to the dirt and bacteria deposited by the occupants, the interiors of cars are subject to degradation by exposure to the more harmful rays of the sun, and the effects of large variations in temperature and moisture content. Over time, porous surfaces such as vinyl and rubber tend to dry out, becoming increasingly brittle and in danger of cracking and splitting. The UV rays from the sun further degrade plastic and vinyl surfaces, resulting in fading and further surface damage. Large variations in moisture content, particularly during the winter months, can encourage the formation of mould and mildew, which can give rise to unpleasant musty odours.
In contrast to other detailing tasks, cleaning and protecting the interior of your is not as straightforward as you might think. If you own a relatively new car or have looked after the interior of your car relatively well, then the chances are the advice given in this guide will be sufficient to enable you to achieve great results. However, if your interior has one or more of the following problems, you would be better off in the first instance employing the services of a professional valeter; badly stained fabrics and/or carpets, obvious mould or mildew, unpleasant musty odours and strong tobacco smoke odours. Such problems need to be remedied using specialist chemicals and professional cleaning equipment, and it is quite easy to make them worse by trying to fix them yourself.
The reasons for this are twofold. Firstly, car manufacturers are increasingly packing more and more electronics into modern cars, including features such as heated seats, air bags and multi-zone in car entertainment systems. Despite the increasing amount of cabling installed in seats and beneath the carpets, and the location of airbag control modules in the footwells, manufacturers still haven't opted to install waterproof fabrics or carpets. This means that the act of shampooing has become a bit of lottery, and professional valeters often have to individually inspect every car to locate the electronics before commencing work. The benefit here is that they know what they are looking for and can act accordingly depending on what they find, plus their work should be insured if things go wrong. The second reason for employing the services of a professional is that they will have specialist equipment, such as shampoo machines, steam machines, foam cleaners and extractors, which enable seats and carpets to be cleaned and dried effectively in a short space of time. In contrast, attempts at home shampooing often leave seats and carpets wet for days on end, which can encourage the formation of mould and mildew, and give rise to unpleasant musty odours.
Another potential minefield is the actual quality of the fabrics and leathers used in modern cars. What appears to be leather these days is often not - it is more likely to be a textured vinyl, particularly when found on the backs of seats and on door cards. Real leather is often only used on the cushion and upright of seats, and even this is often of poor quality when compared to traditional leather. In days of old, manufacturers would take a hide and shave it into three layers. The bottom layer (suede) was discarded and used for other purposes, while the top two layers were used for various parts of vehicle upholstery. However, the modern approach is to swell the hide using a chemical process and then shave it into as many as ten layers using computer-controlled machinery. These thin layers are then pressed and stamped with a leather texture in order to mask any imperfections, and then laminated between a fabric and a clear breathable vinyl. In effect, many modern leathers are actually vinyls with a layer of leather veneer, and are much less robust than traditional leather.
The above problem also extends to the fabrics used in many modern cars, which are often of relatively poor quality and easily stained, even by small amounts of water. The reason for this staining is not well known, but probably due to reactions with chemical residues left over from the manufacturing process. The upshot of the above is that we recommend that you should avoid shampooing or making your upholstery wet, and take great care with any leather. If the interior of your car is in good condition then the following advice will enable you to keep it that way, meaning that you will probably never need to call on the services of a professional. We recommend that you detail the interior of your car on a monthly basis, and clean and condition interior leather on a quarterly basis.
When it actually comes to cleaning the interior the first thing you should do is brush down all fabric surfaces using a soft bristled interior brush and wipe down all hard surfaces using a dry microfibre work towel, in order to transfer loose dust and dirt to the floor area. Brushing really helps to pull fluff and dust out of the fibres of fabrics, and restores an attractive, plush look. The next thing you should do is remove the mats from the car and vacuum the carpets and, if they are covered with fabric, the seats. Again, brushing really helps to loosen dirt from the fibres of carpets and restores a nice appearance to the pile. If your vacuum cleaner has a suitable soft brush attachment this can be used at this stage to carefully clean the vents in the dashboard, otherwise this can be done using a small detailing brush. If you have pets and a pet hair problem to remedy, a rubber bristle brush is ideal, and can be bought from most pet shops
After cleaning and dressing all of the hard interior surfaces, the next thing you should do is clean the insides of the windows. If they are relatively clean they can simply be wiped down using a glass cleaner and a microfibre glass towel. However, if they are grubby or have a distinct haze, it is worth wiping them down first using a damp microfibre work towel. If you are ever left with sticky residues after removing interior window stickers, these can be easily and safely removed using a dab of methylated spirit and a microfibre work towel (don't wash this towel in your washing machine again, instead reserve it for grubby tasks).
After cleaning the insides of the windows you shouldn't need to sit in the seats again to finish the job, so the next step in the process is to tackle any stains in the seat fabrics, or if you have leather seats, clean and condition the leather. In both cases, any cleaning can be safely done using an all purpose cleaner diluted down to the recommended level for interior use - if you have leather seats read the label on the bottle first and make sure it is safe for use on leather. In order to use the cleaner you should dampen a microfibre work towel with it and then wipe it over the surface, rubbing stains gently. Do not saturate the surface - use as little product as possible to ensure a speedy drying time. Once leather seats have been cleaned they should be nourished and protected using a good quality surface dressing, which should be applied using a microfibre pad.
The next step in the process is to clean and protect the door sills, which are often completely overlooked. If the door sills aren't particularly grubby they can be easily cleaned using an all purpose cleaner and a microfibre work towel - it is worth remembering to give the pedals a wipe over at the same time (using an old toothbrush helps if your pedals are heavily textured). If the sills are really grubby, they can be washed down using a microfibre wash mitt and a bucket of suds, and then dried using a heavyweight waffle weave microfibre towel. Once clean and dry, sills should be protected by applying a surface dressing to plastic surfaces and either wax or sealant protection to painted surfaces. In the latter case spray waxes afford a quick and easy means of applying protection.
The penultimate step in the process is to tackle the mats you removed from the car during the initial stages of the process. While you do this, you can also do something about any odours in your carpets by sprinkling over either a household shake n vac style product or bicarbonate of soda, and leaving it to absorb contaminants for a couple of hours. The latter is the better choice, as it is odourless, unlike the household products, which can be a bit flowery. Returning to the mats, the first thing you should do to them is brush them and vacuum them. If they are made of fabric and feel damp after vacuuming, hang them up in a well ventilated place for a couple of hours to dry out. It is a good idea to do this regularly during the winter months, as mats often become sodden at this time of year, and regular drying out will help to prevent the formation of mould and mildew, which can give rise to unpleasant musty odours. If your mats are made of rubber they can be restored to as new condition using an all purpose cleaner and a microfibre work towel - under no circumstances apply any surface dressings to mats (or pedals for that matter). If you opted to treat the carpets for any odours, don't forget to vacuum them again thoroughly before finally refitting the mats.
The final step in the cleaning process is to pack away all of the tools you have used, making sure everything is clean and ready for the next use. All towels and applicator pads should be washed in a washing machine at a low temperature using a gentle non-biological liquid detergent (avoid soap powders and detergents containing bleach or fabric softeners), before allowing everything to dry out naturally. Finally, any fluff and hair lodged in your detailing brushes should be picked out and the vacuum cleaner emptied.