Cars are expensive to run and one of the biggest ongoing costs is petrol. Petrol prices are likely going to continue to rise. I have composed a list of 7 ways to improve your cars fuel economy. These wont make your car run off the smell of an oily rag but they will save you a few bucks each week.
If you are serious about improving your fuel economy the first thing to do is track your current km per litre. Often the trip computer in the car is not the best indicator, I recommend that you fill up, reset your trip meter then drive to near empty. When you fill up divide the litres taken to fill by the kms traveled. This will give you a more accurate baseline to work with.
Keeping your car clean will help to reduce the drag coefficient of your car and therefor reduce the
energy required to keep it in motion. Removing roof racks, spotlights, led bars, caravan mirrors, weather shields and other accessories will help to improve the aerodynamics. Avoid driving around with your windows down.
2 Proper and Regular Maintenance.
Making sure your car is regularly serviced and maintained can help your economy in a number of ways. Fresh Engine oil has less friction, it is easier for your oil pump to pump oil through a clean oil filter. Clean Air filters make it easier for your engine to breath. Damaged or malfunctioning sensors such as an Oxygen sensor can cause your car to run in rich and retard mode consuming a lot more fuel. If your cars computer does not receive engine sensor input it will compensate on the safe side running rich to protect the engine.
3 Reducing your Speed
As your vehicle speed is increased the wind friction increases causing a lowering of fuel efficiency. I have personally found that when on the highway cruising reducing my speed by 4 or 5 km/h will save me around .5L per 100 kms on trips.
4 Changing your Driving style
This is perhaps the most important factor of all. Fast acceleration uses significantly more fuel than slowly accelerating up to speed. Avoid braking and coast for as long as possible when coming to a stop. In a manual transmission car changing up to the highest possible gear without lugging the engine. Lugging is when you put the car under high load at very low RPM. Engine shuddering or vibration can be an indicator that you are lugging your vehicle.
5 Tyre Pressures
Ensuring you are running the correct tyre pressure both prolongs the life of your tyres and reduces the rolling resistance of the tyres on the road. Rotating tyres for even tyre wear as well as ensuring correct balance and alignment will make for a safer and more efficient car.
6 Say No To Accessories
Turn off the air-conditioning in the car if it is not required as the compressor requires a significant amount of energy from the engine. Turn off any accessories that you do not need that are drawing electricity. When electricity is drawn from your car it increases the energy required to rotate the alternator and therefor uses more fuel.
7 Weight Reductions
Have a look through your boot, glovebox, storage compartments and remove anything that is not
required. Replacing heavy components with aluminium, fibreglass or carbon fibre. Carrying around all those extra kilos requires more energy for your car to accelerate up to speed.
A crazy suggestion that I read once was to do your grocery shopping at a store at a higher altitude so that the weight of the groceries would help you coast downhill on the way home. I understand some of these suggestions will make little difference but others are quite significant.
I have found that you could expect a 10-15% improvement in fuel economy by making changes like the ones I have mentioned. Let me know how you go with it or if you have any other ideas for things I have missed.