Have modern cars made DIY servicing impossible?

With an older vehicle, when keeping the service history stamped has no longer become a factor in its value, you might consider servicing yourself. But has increased complexity made DIY servicing impossible?

Look under the bonnet of a car 30 years ago and you could see almost everything you would need to access during a service. However as manufacturers have added more ancillaries, engines bays have become increasingly cramped and plastic engine covers have masked many of the components.

Despite this, under the plastic still exists the basics of a century old design that you can keep running soundly into it’s twilight years with some home maintenance.



I would strongly recommend picking up a Haynes manual for your model before undertaking any jobs and of course be careful when working with fuel, oil and electrics.


Air Filter

The simplest thing to change yourself. The air filter is usually easily accessible and only held in with clips. Keeping your filter clean will reduce your emissions and marginally increase fuel economy.

Time 5 – 10 minutes.

Available online for common car models for as little as £5.


Oil change and filter

Changing the oil is the essential part of any service. For this job you will require ramps or a jack and axle stands, a spanner or socket drive for the sump plug, possibly an oil filter wrench and a funnel for the oil. As cars have added ancillaries and under-trays the filter and sump plug have become more difficult to access.

Time 30 – 40 minutes.

5 Litres of oil is available online from £20 and filters from £5 for common car models.


Fuel Filter

Because this involves the fuel system I would recommend leaving this to garage unless you know what you’re doing. On older cars with low pressure fuel pumps supplying carburetors these were often found in the engine bay. Now with high pressure pumps to supply fuel injection systems they’re mostly found under the car. You will need pliers or a screwdriver depending on the hose clips.

10 – 20 minutes.

£7 – £10 for common models.


Spark Plugs

A weak spark is a common cause of misfires and poor performance. Most engines nowadays are double overhead cam designs with the spark plugs buried in the middle under a plastic engine cover. You will need a spark plug socket and a socket wrench with an extension. You will need to remove the engine cover and ignition leads.

15 – 30 minutes.

£3 – £7 per plug for common models.


Drive Belts

A noisy drive belt can be annoying and a broken one can leave you stranded or worse. Today we see increasingly complicated routing for these belts as they drive more components. Unless you’ve some experience I would recommend leaving this one to the garage.

30 – 60 minutes

£10 – £30 per belt for common models.



A tired battery can give warning signs before it fails with a noticeable whine when starting. Changing it will save a breakdown call out. However if you don’t know what you’re doing, you run the risk of damaging your ecu or worse electrocution. Check your vehicle handbook for any manufacturers recommendations when changing the battery. You may need your radio code handy. Aside from a plastic cover, the battery should be easily accessible. You will most likely require only a 10 mm spanner for the terminals and possibly a socket set with extensions to remove it from the tray.

15 – 20 minutes.

Price for an average car battery £40 – £60 online.


Engine service lights

Resetting these used to be reserved for the garage, using an expensive diagnostic tool. However on board diagnostic tools can now be purchased on eBay for as little as £5. For those not proficient with computers it will still be a complicated job.

10 – 15 minutes, not including reading the instructions.

£5 – £40 for an OBD2 tool on eBay.


For those jobs you simply can’t do, it can often be cost effective ordering servicing parts yourself. This is because some garages will charge a mark up on trade prices or be obliged to use certain brands. By sourcing the parts yourself online you can find some great deals and then just pay labour costs for fitting at the garage.