Useful info about
gas mileage

There are some common misconceptions about fuel economy and just what we can do to improve it in our daily driving. A few of these ideas are left over from our father's time, or maybe even our grandfather's.

One often heard idea is to shift to neutral and coast to a stop. False! If you have a standard transmission this may help, but if like most folks you are driving an automatic shift car you can actually get better economy by leaving it in gear. Modern cars have a feature that will cut the fuel to the injectors when it detects a higher transmission speed than the throttle position is demanding. So on a coast down the fuel shuts off, saving gas and reducing emissions. If you shift to neutral you override this feature.

I have heard it said a clean car gets better mileage. False! According to a test by Car and Driver this is not true. While a clean car may feel better and seem to run better that coat of dirt has no measureable effect on mileage.

Inflating tires to the maximum pressure will improve fuel economy by reducing rolling resistance. False! Popular Mechanics tested this on a drive from Los Angeles to Phoenix and found there was no difference in the economy at specified pressure (30 psi) and maximum pressure (50 psi). The noticeable difference was in ride comfort. At the higher pressure the ride was extremely harsh and uncomfortable.

Fill up in the evening or early morning. False! Consumer Reports debunks this claim. Gas pumps are temperature compensated to pump the same volume regardless of the fuel temperature. Besides, with underground storage the temperature variation in the tank is minimal.

Driving with the A/C off and the windows open saves gas. True and false. Different tests have produced varying results for different models and speeds. In all cases the economy loss with the A/C on was negligible, definitely not enough to give up the cool air in our summer climate.

Roof racks are aerodynamic. False! Even without anything tied to them roof racks can reduce fuel mileage by as much as 5% according the Car and Driver. They tested a Subaru Forrester and found that the drag of the rack reduced economy more as the speed increased.

Convertibles waste gas. True! Surprisingly the loss of economy with the top down is less than the loss from the roof rack test mentioned above, but it is still there. At speeds lower than 35 mph the loss is minor versus having the top and windows up. At higher speeds the waste of gas increases, but then who wants the top down at 70.

The biggest determining factor in fuel economy is the driver. Oh so True! Like it or not we are the biggest enemy of fuel economy. Our driving habits of fast starts, hard stops, long idle times, hard acceleration and unnecessary trips drain our pockets as fast as they drain our tanks.

Summer is almost here!

This year, because of the economy, we may not be driving as much as in the past years, but the summer will be just as hot and long as ever. Our cars will still need the TLC that keeps them running dependably. There are a few areas of care that can really save money by preventing the expensive breakdown that will inevitably follow neglect.

Service the cooling system. The radiator should be drained and flushed every 2 years regardless of what the manufacturer has to say about lifetime coolants. We have seen too many cases of cooling system failure when the owners follow the ridiculously long intervals suggested by most makers. Probably 50% of the engine failures we see are directly related to a cooling system failure. This is when you have the fan belts and cooling hoses checked too.

The air conditioning system should be checked every year, just like the one in your home. Most cars now have an air conditioning cabin filter, again like the one in your home, which should be changed annually. Many newer systems hold only a pound or less of Freon, so if the unit is even a few ounces low it can cause compressor overheating and failure.

The tires and brakes should be looked at. If your tires have not been rotated recently that should be done at the beginning of the summer. Any tire inspection should include the spare too. This also provides a perfect time to inspect the braking system while the wheels are off. If a tire is starting to go bad, due to separation in the tread or wear, they will only be more likely to fail under the higher heat load of summer driving. Almost any brake problem only gets more expensive and dangerous if it is not uncovered early.  

Check all lights. Often in the summer months, even though the sun goes down later in the evening, we are out after dark. Check all of the exterior lights and make sure that they all function. If your headlamps have developed a film on the lens that reduces the amount of light they project consider having the BG headlamp service done. The BG lamp cleaning will restore the lens to almost new condition and greatly improve your ability to see the road at night.

The average battery will last only 3 years in our area. If your battery is older than that it should be replaced before it fails. With all the high tech electronics on cars today a battery failure can result in other components failing too. Much like your home computer these micro processors in your car do not like the voltage spikes or surges that can be caused by a failing battery. If your battery is newer than 3 years old have it tested, cleaned and the liquid level in it checked. At the same time have the charging and starting systems checked.

Most of these important preventive maintenances can be done by a reasonably good do it yourselfer. If you need help with it you can email us at the shop or radio show and we will help you work through things.

If you are not ready to tackle the summer prep for your car call us at the shop and we will be happy to help you with it.

Look in this newsletter for a valuable coupon that will make these services much more affordable.

High Water & Cars Don't Mix!

If you drove through high water during the recent rains...even if you did not stall out, you may have gotten water into your car's mechanical system. Water can infiltrate the transmission, damage brakes, cause electrical problems and, depending on the design of your car, water can get into the engine through the air intake system without you knowing it.

If you car drove through unusually high water it may be wise to have your automotive shop check it out. Simple things like an oil change or transmission service could save you money on future repairs.

If you have questions please call us at Freedom Automotive or email us.